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A vendor sells 50 percent of apples he had and throws away 20 percent of the remainder. Next day he sells 60 percent of the remainder and throws away the rest. What percent of his apples does the vendor throw?
- a)20%
- b)22%
- c)24%
- d)26%
- e)None of these
Correct answer is option 'D'. Can you explain this answer?
A vendor sells 50 percent of apples he had and throws away 20 percent of the remainder. Next day he sells 60 percent of the remainder and throws away the rest. What percent of his apples does the vendor throw?
a)
20%
b)
22%
c)
24%
d)
26%
e)
None of these
|
Machine Experts answered |
Let the total number of apples the vendor initially had be 100 (for simplicity).
On the first day:
The vendor sells 50% of the apples:
Apples sold on day 1 = 50% of 100 = 50
The remaining apples after selling 50% are:
Remaining apples = 100 − 50 = 50
He then throws away 20% of the remaining apples:
Apples thrown away on day 1 = 20% of 50 = 10
The remaining apples after throwing away 20% are:
Remaining apples after day 1 = 50 − 10 = 40
On the second day:
The vendor sells 60% of the remaining apples:
Apples sold on day 2 = 60% of 40 = 24
The remaining apples after selling 60% are:
Remaining apples after selling on day 2 = 40 − 24 = 16
He throws away the rest, which is 16 apples.
Total apples thrown away:
Apples thrown away on day 1 = 10
Apples thrown away on day 2 = 16
Total apples thrown away = 10 + 16 = 26
Percentage of apples thrown away:
Thus, the vendor throws away 26% of his apples.
On the first day:
The vendor sells 50% of the apples:
Apples sold on day 1 = 50% of 100 = 50
The remaining apples after selling 50% are:
Remaining apples = 100 − 50 = 50
He then throws away 20% of the remaining apples:
Apples thrown away on day 1 = 20% of 50 = 10
The remaining apples after throwing away 20% are:
Remaining apples after day 1 = 50 − 10 = 40
On the second day:
The vendor sells 60% of the remaining apples:
Apples sold on day 2 = 60% of 40 = 24
The remaining apples after selling 60% are:
Remaining apples after selling on day 2 = 40 − 24 = 16
He throws away the rest, which is 16 apples.
Total apples thrown away:
Apples thrown away on day 1 = 10
Apples thrown away on day 2 = 16
Total apples thrown away = 10 + 16 = 26
Percentage of apples thrown away:
Thus, the vendor throws away 26% of his apples.
In a library, 30% of the books are in History. 50% of the remaining are in English and 40% of the remaining are in German. The remaining 4200 books are in regional languages. What is the total number of books in library?- a)10000
- b)15000
- c)20000
- d)25000
- e)None of these
Correct answer is option 'C'. Can you explain this answer?
In a library, 30% of the books are in History. 50% of the remaining are in English and 40% of the remaining are in German. The remaining 4200 books are in regional languages. What is the total number of books in library?
a)
10000
b)
15000
c)
20000
d)
25000
e)
None of these
|
|
Machine Experts answered |
Let the total number of books in the library be T.
30% of the books are in History:
History books = 30% of T = 0.30 × T
The remaining books after accounting for History are:
Remaining books = T − 0.30 × T = 0.70 × T
50% of the remaining books are in English:
English books = 50% of the remaining = 0.50 × 0.70 × T = 0.35 × T
After accounting for English books, the remaining books are:
Remaining books after English = 0.70T − 0.35T = 0.35T
40% of the remaining books are in German:
German books = 40% of the remaining = 0.40 × 0.35 × T = 0.14 × T
After accounting for German books, the remaining books are:
Remaining books after German = 0.35T − 0.14T = 0.21T
The remaining 4200 books are in regional languages, so:
0.21 × T = 4200
Solving for T:
T = 4200/0.21 = 20000
Thus, the total number of books in the library is 20,000.
30% of the books are in History:
History books = 30% of T = 0.30 × T
The remaining books after accounting for History are:
Remaining books = T − 0.30 × T = 0.70 × T
50% of the remaining books are in English:
English books = 50% of the remaining = 0.50 × 0.70 × T = 0.35 × T
After accounting for English books, the remaining books are:
Remaining books after English = 0.70T − 0.35T = 0.35T
40% of the remaining books are in German:
German books = 40% of the remaining = 0.40 × 0.35 × T = 0.14 × T
After accounting for German books, the remaining books are:
Remaining books after German = 0.35T − 0.14T = 0.21T
The remaining 4200 books are in regional languages, so:
0.21 × T = 4200
Solving for T:
T = 4200/0.21 = 20000
Thus, the total number of books in the library is 20,000.
A number is first decreased by 25%. The decreased number is then increased by 20%. The resulting number is less than the original number by 40. Then the original number is –
- a)100
- b)200
- c)300
- d)400
- e)None of these
Correct answer is option 'D'. Can you explain this answer?
A number is first decreased by 25%. The decreased number is then increased by 20%. The resulting number is less than the original number by 40. Then the original number is –
a)
100
b)
200
c)
300
d)
400
e)
None of these
|
Cstoppers Instructors answered |
Let the number is a a – (75/100)*a*(120/100) = 40 we will get a = 400
A man has 4000 rupees in his account two years ago. In the first year he deposited 20 percent of the amount in his account. In the next year he deposited 10 percent of the increased amount in the account. Find the total amount in the account of the person after 2 years.- a)6650
- b)5280
- c)5740
- d)5840
- e)None of these
Correct answer is option 'B'. Can you explain this answer?
A man has 4000 rupees in his account two years ago. In the first year he deposited 20 percent of the amount in his account. In the next year he deposited 10 percent of the increased amount in the account. Find the total amount in the account of the person after 2 years.
a)
6650
b)
5280
c)
5740
d)
5840
e)
None of these
|
Anaya Patel answered |
Answer – b) 5280 Explanation : 4000 + 800 + 480 = 5280
40% of the women are above 30 years of age and 80 percent of the women are less than or equal to 50 years of age. 20 percent of all women play basketball.If 30 percent of the women above the age of 50 plays basketball, what percent of players are less than or equal to 50 years?- a)50%
- b)60%
- c)70%
- d)80%
- e)None of these
Correct answer is option 'C'. Can you explain this answer?
40% of the women are above 30 years of age and 80 percent of the women are less than or equal to 50 years of age. 20 percent of all women play basketball.If 30 percent of the women above the age of 50 plays basketball, what percent of players are less than or equal to 50 years?
a)
50%
b)
60%
c)
70%
d)
80%
e)
None of these
|
|
Machine Experts answered |
Let the total number of women be 100 (for simplicity).
Women above 30 years of age:
40% of the women are above 30 years of age, which means:
Women above 30 years = 40% of 100 = 40 women
Women less than or equal to 50 years of age:
80% of the women are less than or equal to 50 years of age, which means:
Women less than or equal to 50 years = 80% of 100 = 80 women
Women above 50 years of age:
Since 80% are less than or equal to 50 years, the remaining 20% are above 50 years of age, which means:
Women above 50 years = 20% of 100 = 20 women
Women who play basketball:
20% of all women play basketball, which means:
Total basketball players = 20% of 100 = 20 women
Women above 50 years of age who play basketball:
30% of the women above 50 years play basketball, which means:
Basketball players above 50 years = 30% of 20 = 6 women
Women less than or equal to 50 years who play basketball:
The total number of basketball players is 20, and 6 of them are above 50 years of age.
Therefore, the number of players less than or equal to 50 years of age is:
Basketball players less than or equal to 50 years = 20 − 6 = 14 women
Percentage of players who are less than or equal to 50 years of age:
Percentage of players less than or equal to 50 years =
Thus, 70% of the basketball players are less than or equal to 50 years of age.
Women above 30 years of age:
40% of the women are above 30 years of age, which means:
Women above 30 years = 40% of 100 = 40 women
Women less than or equal to 50 years of age:
80% of the women are less than or equal to 50 years of age, which means:
Women less than or equal to 50 years = 80% of 100 = 80 women
Women above 50 years of age:
Since 80% are less than or equal to 50 years, the remaining 20% are above 50 years of age, which means:
Women above 50 years = 20% of 100 = 20 women
Women who play basketball:
20% of all women play basketball, which means:
Total basketball players = 20% of 100 = 20 women
Women above 50 years of age who play basketball:
30% of the women above 50 years play basketball, which means:
Basketball players above 50 years = 30% of 20 = 6 women
Women less than or equal to 50 years who play basketball:
The total number of basketball players is 20, and 6 of them are above 50 years of age.
Therefore, the number of players less than or equal to 50 years of age is:
Basketball players less than or equal to 50 years = 20 − 6 = 14 women
Percentage of players who are less than or equal to 50 years of age:
Percentage of players less than or equal to 50 years =
Thus, 70% of the basketball players are less than or equal to 50 years of age.
60 percent of the employees of a company are women and 75% of the women earn 20000 or more in a month. Total number of employees who earns more than 20000 per month in the company is 60 percent of the total employees.What fraction of men earns less than 20000 per month?- a)5/8
- b)5/7
- c)1/5
- d)3/4
- e)None of these
Correct answer is option 'A'. Can you explain this answer?
60 percent of the employees of a company are women and 75% of the women earn 20000 or more in a month. Total number of employees who earns more than 20000 per month in the company is 60 percent of the total employees.What fraction of men earns less than 20000 per month?
a)
5/8
b)
5/7
c)
1/5
d)
3/4
e)
None of these
|
|
Machine Experts answered |
Total employees = 100 (for simplicity).
Number of women = 60% of 100 = 60 women.
Number of men = 40% of 100 = 40 men.
75% of the women earn 20,000 or more:
Women earning 20,000 or more = 75% of 60 = 0.75 × 60 = 45 women.
Total number of employees earning more than 20,000 per month is 60% of the total employees:
Employees earning more than 20,000 = 60% of 100 = 60 employees.
Out of these 60 employees, 45 are women, so the remaining 15 must be men:
Men earning more than 20,000 = 15 men.
The total number of men is 40, and 15 men earn more than 20,000, so the number of men earning less than 20,000 is:
Men earning less than 20,000 = 40 − 15 = 25 men.
The fraction of men earning less than 20,000 is:
Fraction = 25/40 = 5 / 8
Thus, the correct answer is A: 5/8
Number of women = 60% of 100 = 60 women.
Number of men = 40% of 100 = 40 men.
75% of the women earn 20,000 or more:
Women earning 20,000 or more = 75% of 60 = 0.75 × 60 = 45 women.
Total number of employees earning more than 20,000 per month is 60% of the total employees:
Employees earning more than 20,000 = 60% of 100 = 60 employees.
Out of these 60 employees, 45 are women, so the remaining 15 must be men:
Men earning more than 20,000 = 15 men.
The total number of men is 40, and 15 men earn more than 20,000, so the number of men earning less than 20,000 is:
Men earning less than 20,000 = 40 − 15 = 25 men.
The fraction of men earning less than 20,000 is:
Fraction = 25/40 = 5 / 8
Thus, the correct answer is A: 5/8
Alisha goes to a supermarket and bought things worth rupees 60, out of which 40 paise went on sales tax. If the tax rate is 10 percent, then what was the cost of tax free items?- a)54.60
- b)55.60
- c)56.60
- d)57.60
- e)None of these
Correct answer is option 'B'. Can you explain this answer?
Alisha goes to a supermarket and bought things worth rupees 60, out of which 40 paise went on sales tax. If the tax rate is 10 percent, then what was the cost of tax free items?
a)
54.60
b)
55.60
c)
56.60
d)
57.60
e)
None of these
|
|
Machine Experts answered |
Total cost of items = ₹60.
Sales tax paid = 40 paise = ₹0.40.
Tax rate = 10%. So, the tax amount is 10% of the cost of taxed items (denoted as T).
The sales tax equation is:
Solving for T:
Solving for T:
Now, the cost of tax-free items is:
Cost of tax-free items = 60 − T − Sales tax = 60 − 4 − 0.40 = 55.60 rupees.
Thus, the cost of tax-free items is ₹55.60.
Cost of tax-free items = 60 − T − Sales tax = 60 − 4 − 0.40 = 55.60 rupees.
Thus, the cost of tax-free items is ₹55.60.
In an election contested by two parties A and B, party A secured 25 percent of the total votes more than Party B. If party B gets 15000 votes. By how much votes does party B loses the election?- a)8000
- b)10000
- c)12000
- d)15000
- e)None of these
Correct answer is option 'B'. Can you explain this answer?
In an election contested by two parties A and B, party A secured 25 percent of the total votes more than Party B. If party B gets 15000 votes. By how much votes does party B loses the election?
a)
8000
b)
10000
c)
12000
d)
15000
e)
None of these
|
KS Coaching Center answered |
Answer – b) 10000 Explanation : Let total votes = T and party B gets 15000 votes then party A will get T -15000 votes T – 15000 – 15000 = 25T/100
T = 40000, so A get 25000 and B gets 15000 votes, so difference = 10000
T = 40000, so A get 25000 and B gets 15000 votes, so difference = 10000
A man spends 60% of his income. His income is increased by 20% and his expenditure also increases by 10%. Find the percentage decrease in his saving?- a)10%
- b)15%
- c)20%
- d)25%
- e)None of these
Correct answer is option 'A'. Can you explain this answer?
A man spends 60% of his income. His income is increased by 20% and his expenditure also increases by 10%. Find the percentage decrease in his saving?
a)
10%
b)
15%
c)
20%
d)
25%
e)
None of these
|
Rhea Reddy answered |
Answer – a) 10% Explanation : Let initially income is 100. So, expenditure = 60 and saving = 40 now income is increased by 20% i.e. 120. So, expenditure = (70/100)*120 = 84 and saving = 36 so % percent decrease in saving = (4/40)*100 = 10%
The population of a village has increased annually at the rate of 20%. If at the end of 3 years it is 21600, the population in the beginning of the first year?- a)10000
- b)12500
- c)15000
- d)17500
- e)None of these
Correct answer is option 'B'. Can you explain this answer?
The population of a village has increased annually at the rate of 20%. If at the end of 3 years it is 21600, the population in the beginning of the first year?
a)
10000
b)
12500
c)
15000
d)
17500
e)
None of these
|
Divey Sethi answered |
We can use the formula for compound growth to find the initial population:
where:
- P is the final population (21600)
- P0 is the initial population (what we want to find)
- r is the annual growth rate (20% or 0.20)
- n is the number of years (3)
Plug in the known values:
Simplify and solve for P0:
Simplify and solve for P0:
30 litre of solution contains alcohol and water in the ratio 2:3. How much alcohol must be added to the solution to make a solution containing 60% of alcohol?- a)10
- b)12
- c)14
- d)15
- e)None of these
Correct answer is option 'D'. Can you explain this answer?
30 litre of solution contains alcohol and water in the ratio 2:3. How much alcohol must be added to the solution to make a solution containing 60% of alcohol?
a)
10
b)
12
c)
14
d)
15
e)
None of these
|
|
Machine Experts answered |
The initial solution contains 30 liters, with alcohol and water in the ratio 2:3.
The amount of alcohol in the solution is:
The amount of water in the solution is:
The amount of water in the solution is:
We need to add some amount of alcohol (let it be x) to make the alcohol content 60% of the total solution.
After adding x liters of alcohol, the new total volume of the solution will be 30 + x liters, and the amount of alcohol will be 12 + x liters.
The concentration of alcohol should be 60%, so:
Solving the equation:
Solving the equation:
Thus, 15 liters of alcohol must be added to the solution.
A got 30% of the maximum marks in an examination and failed by 10 marks. However, B who took the same examination got 40% of the total marks and got 15 marks more than the passing marks. What were the passing marks in the examination?- a)65
- b)75
- c)80
- d)None of these
Correct answer is option 'D'. Can you explain this answer?
A got 30% of the maximum marks in an examination and failed by 10 marks. However, B who took the same examination got 40% of the total marks and got 15 marks more than the passing marks. What were the passing marks in the examination?
a)
65
b)
75
c)
80
d)
None of these
|
Engineers Adda answered |
(30/100)*T = P -10
(40/100)*T = P + 15
U will get P = 85
(40/100)*T = P + 15
U will get P = 85
Weights of two friends A and B are in the ratio of 1 : 2. A’s weight increases by 20% and the total weight of A and B together becomes 60 kg, with an increase of 30%. By what percent the weight of B increase?
- a)30%
- b)35%
- c)40%
- d)45%
- e)None of these
Correct answer is option 'B'. Can you explain this answer?
Weights of two friends A and B are in the ratio of 1 : 2. A’s weight increases by 20% and the total weight of A and B together becomes 60 kg, with an increase of 30%. By what percent the weight of B increase?
a)
30%
b)
35%
c)
40%
d)
45%
e)
None of these
|
|
KS Coaching Center answered |
Let the original weights of A and B be A and B, respectively. Since the ratio of their weights is 1 : 2, we can say:
A = x and B = 2x
A’s weight increases by 20%, so the new weight of A is:
New weight of A = A + 20% of A = x + 0.20x = 1.2x
The total weight of A and B after the increase is 60 kg, and it is also given that the total weight increased by 30%. Therefore, the original total weight of A and B was:
Original total weight = 60/1.30 = 46.15 kg (approximately)
The original total weight of A and B is also A + B = x + 2x = 3x, so:
3 x = 46.15 ⇒ x = 46.15/3 = 15.38 kg (approximately)
So, A’s original weight is approximately 15.38 kg, and B’s original weight is:
B = 2x = 2 × 15.38 = 30.76 kg (approximately)
The new total weight is 60 kg, and the new weight of A is 1.2x = 1.2 × 15.38 = 18.46 kg. Therefore, the new weight of B is:
New weight of B = 60 − 18.46 = 41.54 kg (approximately)
Now, we can calculate the percentage increase in B’s weight:
A = x and B = 2x
A’s weight increases by 20%, so the new weight of A is:
New weight of A = A + 20% of A = x + 0.20x = 1.2x
The total weight of A and B after the increase is 60 kg, and it is also given that the total weight increased by 30%. Therefore, the original total weight of A and B was:
Original total weight = 60/1.30 = 46.15 kg (approximately)
The original total weight of A and B is also A + B = x + 2x = 3x, so:
3 x = 46.15 ⇒ x = 46.15/3 = 15.38 kg (approximately)
So, A’s original weight is approximately 15.38 kg, and B’s original weight is:
B = 2x = 2 × 15.38 = 30.76 kg (approximately)
The new total weight is 60 kg, and the new weight of A is 1.2x = 1.2 × 15.38 = 18.46 kg. Therefore, the new weight of B is:
New weight of B = 60 − 18.46 = 41.54 kg (approximately)
Now, we can calculate the percentage increase in B’s weight:
Thus, B’s weight increased by 35%.
The population of a village has increased annually at the rate of 20%. If at the end of 3 years it is 21600, the population in the beginning of the first year?- a)10000
- b)12500
- c)15000
- d)17500
Correct answer is option 'B'. Can you explain this answer?
The population of a village has increased annually at the rate of 20%. If at the end of 3 years it is 21600, the population in the beginning of the first year?
a)
10000
b)
12500
c)
15000
d)
17500
|
Bayshore Academy answered |
- The population increases by 20% annually, meaning it multiplies by 1.20 each year.
- After 3 years, the population is 21600.
- Using the compound growth formula P=P0(1+r)t, where P = 21600, r = 0.20, and t = 3, we calculate the initial population P0.
- Solving 21600=P0 x (1.20)3, we find P0 = 12500.
- The initial population is therefore 12500.
The number of seats in a cinema hall is decreased by 8% and also the price of the ticket is increased by 4 percent. What is the effect on the revenue collected?- a)increase 4.32%
- b)decrease 4.32%
- c)increase 3.32 percent
- d)decrease 3.32%
- e)None of these
Correct answer is option 'B'. Can you explain this answer?
The number of seats in a cinema hall is decreased by 8% and also the price of the ticket is increased by 4 percent. What is the effect on the revenue collected?
a)
increase 4.32%
b)
decrease 4.32%
c)
increase 3.32 percent
d)
decrease 3.32%
e)
None of these
|
|
Cstoppers Instructors answered |
Answer – b) decrease 4.32% Explanation : Let initially seats are 100 and price of each seat is 100, so total initial revenue = 10000
now, seats are 92 and price of each seat = 104, so total revenue = 92*104 = 9568 so percent change in revenue = (432/10000)*100 = 4.32 decrease
now, seats are 92 and price of each seat = 104, so total revenue = 92*104 = 9568 so percent change in revenue = (432/10000)*100 = 4.32 decrease
The marked price of an article is 20% higher than the cost price. A discount of 20% is given on the marked price. In this transaction the seller- a)bears no loss no profit
- b)losses 4%
- c)gain 4%
- d)losses 1%
- e)None of these
Correct answer is option 'B'. Can you explain this answer?
The marked price of an article is 20% higher than the cost price. A discount of 20% is given on the marked price. In this transaction the seller
a)
bears no loss no profit
b)
losses 4%
c)
gain 4%
d)
losses 1%
e)
None of these
|
Faizan Khan answered |
Answer – b) losses 4% Explanation : let cost price = 100 so, marked price = 120 now discount of 20% is given, so sp = 120*80/100 = 96 so % loss = (4/100)*100 = 4 percent
12 percent of the voters in an election did not cast their votes. In this election there are only two candidates. The winner by obtaining 45% of the total votes and defeated his rival by 2000 votes. The total number of votes in the election- a)50000
- b)75000
- c)100000
- d)125000
- e)None of these
Correct answer is option 'C'. Can you explain this answer?
12 percent of the voters in an election did not cast their votes. In this election there are only two candidates. The winner by obtaining 45% of the total votes and defeated his rival by 2000 votes. The total number of votes in the election
a)
50000
b)
75000
c)
100000
d)
125000
e)
None of these
|
|
Cstoppers Instructors answered |
12% percent didn’t cast their vote. 45% of total votes get by the winning candidates, so remaining 43% will be scored by his rival. So, (45/100 -43/100)*P = 2000
P = 100000
P = 100000
In an examination 70% candidates passed in prelims and 55% candidates passed in Mains. If 62% candidates passed in both these subjects, then what per cent of candidates failed in both the exams?- a)37%
- b)26%
- c)43%
- d)15%
- e)None of these
Correct answer is option 'A'. Can you explain this answer?
In an examination 70% candidates passed in prelims and 55% candidates passed in Mains. If 62% candidates passed in both these subjects, then what per cent of candidates failed in both the exams?
a)
37%
b)
26%
c)
43%
d)
15%
e)
None of these
|
|
Rajeev Kumar answered |
Answer – 1.37% Explanation : Students passed in Prelims = 70% Students passed in Mains = 55% Students passed in both = 62% No of students passed in at least one subject = (70+55)-62 = 63%. students failed in both subjects = 100-63 = 37%.
In a factory there are three types of bulbs L1, L2 and L3 which produces 20%, 15% and 32% of the total products respectively. L1, L2 and L3 produces 3%, 7% and 2% defective products, respectively. Find the percentage of nondefective products ?- a)46%
- b)30%
- c)53%
- d)64%
- e)None of these
Correct answer is option 'D'. Can you explain this answer?
In a factory there are three types of bulbs L1, L2 and L3 which produces 20%, 15% and 32% of the total products respectively. L1, L2 and L3 produces 3%, 7% and 2% defective products, respectively. Find the percentage of nondefective products ?
a)
46%
b)
30%
c)
53%
d)
64%
e)
None of these
|
|
Faizan Khan answered |
Answer – 4.64% Explanation : (20*0.97)+(15*0.93)+(32*0.98) = 19.4+13.95+31.36
= 64.71
= 64.71
When the price of rice is increased by 30 percent, a family reduces its consumption such that the expenditure is only 20 percent more than before. If 50 kg of rice is consumed by family before, then find the new consumption of family (approx.)- a)43kg
- b)44kg
- c)45kg
- d)46kg
- e)None of these
Correct answer is option 'D'. Can you explain this answer?
When the price of rice is increased by 30 percent, a family reduces its consumption such that the expenditure is only 20 percent more than before. If 50 kg of rice is consumed by family before, then find the new consumption of family (approx.)
a)
43kg
b)
44kg
c)
45kg
d)
46kg
e)
None of these
|
|
Rajeev Kumar answered |
Answer – d) 46kg Explanation : Suppose initially price per kg of rice is 100 then their expenditure is 5000.
Now their expenditure is only increased by only 20% i.e – 6000.
Increased price of rice = 130.
So new consumption = 6000/130 = 46
Now their expenditure is only increased by only 20% i.e – 6000.
Increased price of rice = 130.
So new consumption = 6000/130 = 46
In a class of 60 students , 40% of the students passed in Reasoning, 5% of the students failed in Quants and Reasoning, and 20% of the students passed in both the subjects. Find the number of student passed only in Quants?
- a)17
- b)33
- c)23
- d)37
Correct answer is option 'B'. Can you explain this answer?
In a class of 60 students , 40% of the students passed in Reasoning, 5% of the students failed in Quants and Reasoning, and 20% of the students passed in both the subjects. Find the number of student passed only in Quants?
a)
17
b)
33
c)
23
d)
37
|
Crack Gate answered |
Total students=60
Failed in both=5% of 60=3
Passed in both=20% of 60=12
Passed in reasoning=50% of 60=24
Those passed only in reasoning =24-12=12 students.
Passed only in Quants=60-(12+12+3)=33
Failed in both=5% of 60=3
Passed in both=20% of 60=12
Passed in reasoning=50% of 60=24
Those passed only in reasoning =24-12=12 students.
Passed only in Quants=60-(12+12+3)=33
In a class, 60% of the students are boys and in an examination, 80% of the girls scored more than 40 marks(Maximum Marks:150). If 60% of the total students scored more than 40 marks in the same exam, what is the fraction of the boys who scored 40 marks or less.- a)8/15
- b)7/15
- c)4/5
- d)1/5
Correct answer is option 'A'. Can you explain this answer?
In a class, 60% of the students are boys and in an examination, 80% of the girls scored more than 40 marks(Maximum Marks:150). If 60% of the total students scored more than 40 marks in the same exam, what is the fraction of the boys who scored 40 marks or less.
a)
8/15
b)
7/15
c)
4/5
d)
1/5
|
|
Engineers Adda answered |
Assume Total no of students = 100
60% of the students are boys. so Boys=60,Girls=40
No. of girls who scored more than 40 marks = 80% of girls = 80% of 40 = 32.
No. of students who scored more than 40 marks = 60% of Total Students = 60
Therefore No. of boys who scored more than 40 marks = 60-32=28
No. of boys who scored less= Total boys – Boys(scored more) = 60-28=32
Fraction=(scored less)/Total boys = 32/60 =8/15
60% of the students are boys. so Boys=60,Girls=40
No. of girls who scored more than 40 marks = 80% of girls = 80% of 40 = 32.
No. of students who scored more than 40 marks = 60% of Total Students = 60
Therefore No. of boys who scored more than 40 marks = 60-32=28
No. of boys who scored less= Total boys – Boys(scored more) = 60-28=32
Fraction=(scored less)/Total boys = 32/60 =8/15
2000 sweets need to be distributed equally among the school students in such a way that each student gets sweet equal to 20% of total students. Then the number of sweets, each student gets.
- a)50
- b)20
- c)120
- d)150
Correct answer is option 'B'. Can you explain this answer?
2000 sweets need to be distributed equally among the school students in such a way that each student gets sweet equal to 20% of total students. Then the number of sweets, each student gets.
a)
50
b)
20
c)
120
d)
150
|
Gate Funda answered |
(20/100)*t*t = 2000 (total students = t)
Alisha goes to a supermarket and bought things worth rupees 60, out of which 40 paise went on sales tax. If the tax rate is 10 percent, then what was the cost of tax free items?- a)54.60
- b)55.60
- c)56.60
- d)57.60
Correct answer is option 'B'. Can you explain this answer?
Alisha goes to a supermarket and bought things worth rupees 60, out of which 40 paise went on sales tax. If the tax rate is 10 percent, then what was the cost of tax free items?
a)
54.60
b)
55.60
c)
56.60
d)
57.60
|
Niharika Basu answered |
Calculation of Tax-Free Items Cost:
Explanation:
- Total cost of items = Rs. 60
- Sales tax = 40 paise
- Tax rate = 10%
Step 1: Calculate the total tax amount
- Tax rate = 10%
- Total cost of items = Rs. 60
- Tax amount = 10% of Rs. 60 = Rs. 6
Step 2: Convert the tax amount to paise
- 1 Rupee = 100 paise
- Rs. 6 = 6 * 100 = 600 paise
Step 3: Calculate the tax-free items cost
- Total cost of items = Rs. 60 = 6000 paise
- Sales tax = 40 paise
- Total tax amount = 600 paise
- Cost of tax-free items = Total cost of items - Total tax amount
- Cost of tax-free items = 6000 paise - 600 paise = 5400 paise = Rs. 54
Therefore, the cost of the tax-free items is Rs. 54.60, which is option 'B'.
Explanation:
- Total cost of items = Rs. 60
- Sales tax = 40 paise
- Tax rate = 10%
Step 1: Calculate the total tax amount
- Tax rate = 10%
- Total cost of items = Rs. 60
- Tax amount = 10% of Rs. 60 = Rs. 6
Step 2: Convert the tax amount to paise
- 1 Rupee = 100 paise
- Rs. 6 = 6 * 100 = 600 paise
Step 3: Calculate the tax-free items cost
- Total cost of items = Rs. 60 = 6000 paise
- Sales tax = 40 paise
- Total tax amount = 600 paise
- Cost of tax-free items = Total cost of items - Total tax amount
- Cost of tax-free items = 6000 paise - 600 paise = 5400 paise = Rs. 54
Therefore, the cost of the tax-free items is Rs. 54.60, which is option 'B'.
The ratio of the number of boys and girls in a school is 3:2. If 20% of the boys and 25% of the girls are scholarship holders, the percentage of the students who are not scholarship holders is:- a)30%
- b)60%
- c)75%
- d)78%
Correct answer is option 'D'. Can you explain this answer?
The ratio of the number of boys and girls in a school is 3:2. If 20% of the boys and 25% of the girls are scholarship holders, the percentage of the students who are not scholarship holders is:
a)
30%
b)
60%
c)
75%
d)
78%
|
Telecom Tuners answered |
Consider Total no of students = 100
Ratio is 3:2 i.e Boys=60 and Girls=40
20% of boys who get scholarship = 60*20/100=12%
25% of girls who get scholarship = 40*25/100 =10%
Therefore % of students who do not get scholarship =100-(12+10) = 78%
Ratio is 3:2 i.e Boys=60 and Girls=40
20% of boys who get scholarship = 60*20/100=12%
25% of girls who get scholarship = 40*25/100 =10%
Therefore % of students who do not get scholarship =100-(12+10) = 78%
The number of seats in a cinema hall is decreased by 8% and also the price of the ticket is increased by 4 percent. What is the effect on the revenue collected?- a)increase 4.32%
- b)decrease 4.32%
- c)increase 3.32 percent
- d)decrease 3.32%
Correct answer is option 'B'. Can you explain this answer?
The number of seats in a cinema hall is decreased by 8% and also the price of the ticket is increased by 4 percent. What is the effect on the revenue collected?
a)
increase 4.32%
b)
decrease 4.32%
c)
increase 3.32 percent
d)
decrease 3.32%
|
EduRev GATE answered |
Let initially seats are 100 and price of each seat is 100, so total initial revenue = 10000
now, seats are 92 and price of each seat = 104, so total revenue = 92*104 = 9568
so percent change in revenue = (432/10000)*100 = 4.32 decrease
now, seats are 92 and price of each seat = 104, so total revenue = 92*104 = 9568
so percent change in revenue = (432/10000)*100 = 4.32 decrease
The population of a town is 15000. It increases by 10 percent in the first year and 20 percent in the second year. But in the third year it decreases by 10 percent. What will be the population after 3 years.- a)16820
- b)15820
- c)17820
- d)19820
Correct answer is option 'C'. Can you explain this answer?
The population of a town is 15000. It increases by 10 percent in the first year and 20 percent in the second year. But in the third year it decreases by 10 percent. What will be the population after 3 years.
a)
16820
b)
15820
c)
17820
d)
19820
|
|
Telecom Tuners answered |
15000*(11/10)*(12/10)*(9/10) = 17820
60 percent of the employees of a company are women and 75% of the women earn 20000 or more in a month. Total number of employees who earns more than 20000 per month in the company is 60 percent of the total employees. What fraction of men earns less than 20000 per month?- a)5/8
- b)5/7
- c)1/5
- d)3/4
Correct answer is option 'A'. Can you explain this answer?
60 percent of the employees of a company are women and 75% of the women earn 20000 or more in a month. Total number of employees who earns more than 20000 per month in the company is 60 percent of the total employees. What fraction of men earns less than 20000 per month?
a)
5/8
b)
5/7
c)
1/5
d)
3/4
|
|
Telecom Tuners answered |
let total employees are 100
males = 40 and females = 60 (45 women earns more than 20000)
total 60 employee earns more than 20000 per month, so number of males earns more than 20000 is 15
so fraction = 25/40 = 5/8
males = 40 and females = 60 (45 women earns more than 20000)
total 60 employee earns more than 20000 per month, so number of males earns more than 20000 is 15
so fraction = 25/40 = 5/8
720 sweets are distributed equally among the children in such a way that the number of sweets given to each child is equal to 20% of the total number of children. How many sweets did each child get?- a)11
- b)15
- c)12
- d)14
- e)None of these
Correct answer is option 'C'. Can you explain this answer?
720 sweets are distributed equally among the children in such a way that the number of sweets given to each child is equal to 20% of the total number of children. How many sweets did each child get?
a)
11
b)
15
c)
12
d)
14
e)
None of these
|
Mita Mehta answered |
The population of a town is 15000. It increases by 10 percent in the first year and 20 percent in the second year. But in the third year it decreases by 10 percent. What will be the population after 3 years.- a)16820
- b)15820
- c)17820
- d)19820
- e)None of these
Correct answer is option 'C'. Can you explain this answer?
The population of a town is 15000. It increases by 10 percent in the first year and 20 percent in the second year. But in the third year it decreases by 10 percent. What will be the population after 3 years.
a)
16820
b)
15820
c)
17820
d)
19820
e)
None of these
|
Nikita Singh answered |
Answer – c) 17820 Explanation : 15000*(11/10)*(12/10)*(9/10) = 17820
Fresh fruits contain 75% while dry fruits contain 20% water. If the weight of dry fruits is 300 kg, what was its total weight when it was fresh?- a)900kg
- b)850kg
- c)920kg
- d)960kg
Correct answer is option 'D'. Can you explain this answer?
Fresh fruits contain 75% while dry fruits contain 20% water. If the weight of dry fruits is 300 kg, what was its total weight when it was fresh?
a)
900kg
b)
850kg
c)
920kg
d)
960kg
|
|
Engineers Adda answered |
Quantity of water in 300 kg dry fruits, = (20 /100) *300 = 60 kg
Quantity of fruit alone= 300-60 =240 kg
25 kg fruit piece in 100 kg fresh fruits
For 240 = (100 *240)/25 = 960 kg.
Quantity of fruit alone= 300-60 =240 kg
25 kg fruit piece in 100 kg fresh fruits
For 240 = (100 *240)/25 = 960 kg.
In a college election 35% voted for Person A, whereas 42% voted for Person B. The remaining people were not vote to any person. If the difference between those who vote for Person B in the election and those who are uncertain was 570, how many people are participated in the college election?
- a)1500
- b)3000
- c)2100
- d)1700
Correct answer is option 'B'. Can you explain this answer?
In a college election 35% voted for Person A, whereas 42% voted for Person B. The remaining people were not vote to any person. If the difference between those who vote for Person B in the election and those who are uncertain was 570, how many people are participated in the college election?
a)
1500
b)
3000
c)
2100
d)
1700
|
|
Engineers Adda answered |
Let the number of individuals involved in election be x.
Percentage of those who were not vote = 100-(35+42) = 23%
The difference between those who voted
42% of x – 23% of x = 570
19% of x = 570
x=570*100/19 = 3000
Percentage of those who were not vote = 100-(35+42) = 23%
The difference between those who voted
42% of x – 23% of x = 570
19% of x = 570
x=570*100/19 = 3000
A reduction of 20% in the price of rice enables a housewife to buy 5 kg more for rupees 1200. The reduced price per kg of rice- a)36
- b)45
- c)48
- d)60
- e)None of these
Correct answer is option 'C'. Can you explain this answer?
A reduction of 20% in the price of rice enables a housewife to buy 5 kg more for rupees 1200. The reduced price per kg of rice
a)
36
b)
45
c)
48
d)
60
e)
None of these
|
Abhiram Mehra answered |
Understanding the Problem
A housewife can buy more rice after a 20% price reduction. We need to determine the new price per kg of rice after this reduction.
Initial Setup
- Let the original price of rice per kg be "P".
- After a 20% reduction, the new price becomes 0.8P.
- The housewife spends 1200 rupees.
Equations Setup
- Originally, for 1200 rupees, she could buy 1200/P kg of rice.
- After the price reduction, she can buy 1200/(0.8P) kg of rice.
Difference in Quantity
- The difference in quantity purchased is given as 5 kg:
1200/(0.8P) - 1200/P = 5
Solving the Equation
1. Simplify the left-hand side:
- Find a common denominator: (0.8P)(P) = 0.8P².
- The equation becomes:
(1200P - 1200 * 0.8P) / (0.8P²) = 5
2. This simplifies to:
(1200P - 960P) / (0.8P²) = 5
- Resulting in:
240P / (0.8P²) = 5
3. Cross-multiplying gives:
240P = 5 * 0.8P²
4. Rearranging leads to:
0.8P² - 240P = 0
Factoring
- Factoring out P:
P(0.8P - 240) = 0
- This implies:
0.8P = 240 => P = 240 / 0.8 = 300
Finding the Reduced Price
- The reduced price per kg is:
0.8P = 0.8 * 300 = 240
- Therefore, the reduced price per kg of rice is:
240 / 5 = 48
Conclusion
The reduced price per kg of rice is 48 rupees, confirming that the correct answer is option 'C'.
A housewife can buy more rice after a 20% price reduction. We need to determine the new price per kg of rice after this reduction.
Initial Setup
- Let the original price of rice per kg be "P".
- After a 20% reduction, the new price becomes 0.8P.
- The housewife spends 1200 rupees.
Equations Setup
- Originally, for 1200 rupees, she could buy 1200/P kg of rice.
- After the price reduction, she can buy 1200/(0.8P) kg of rice.
Difference in Quantity
- The difference in quantity purchased is given as 5 kg:
1200/(0.8P) - 1200/P = 5
Solving the Equation
1. Simplify the left-hand side:
- Find a common denominator: (0.8P)(P) = 0.8P².
- The equation becomes:
(1200P - 1200 * 0.8P) / (0.8P²) = 5
2. This simplifies to:
(1200P - 960P) / (0.8P²) = 5
- Resulting in:
240P / (0.8P²) = 5
3. Cross-multiplying gives:
240P = 5 * 0.8P²
4. Rearranging leads to:
0.8P² - 240P = 0
Factoring
- Factoring out P:
P(0.8P - 240) = 0
- This implies:
0.8P = 240 => P = 240 / 0.8 = 300
Finding the Reduced Price
- The reduced price per kg is:
0.8P = 0.8 * 300 = 240
- Therefore, the reduced price per kg of rice is:
240 / 5 = 48
Conclusion
The reduced price per kg of rice is 48 rupees, confirming that the correct answer is option 'C'.
The prices of two articles are in the ratio 3 : 4. If the price of the first article be increased by 10% and that of the second by Rs. 4, the original ratio remains the same. The original price of the second article is:- a)Rs.40
- b)Rs.35
- c)Rs.10
- d)Rs.30
Correct answer is option 'A'. Can you explain this answer?
The prices of two articles are in the ratio 3 : 4. If the price of the first article be increased by 10% and that of the second by Rs. 4, the original ratio remains the same. The original price of the second article is:
a)
Rs.40
b)
Rs.35
c)
Rs.10
d)
Rs.30
|
Tarun Chawla answered |
Given:
The prices of two articles are in the ratio 3 : 4.
Let:
Let the original price of the first article be 3x and the original price of the second article be 4x.
According to the question:
If the price of the first article is increased by 10%, the new price becomes 3.3x.
If the price of the second article is increased by Rs. 4, the new price becomes 4x + 4.
Given:
The new ratio of the prices is still 3.3 : (4x + 4).
Equating the ratios:
3.3 / (4x + 4) = 3 / 4
Solving the equation:
12.4 = 3(4x + 4)
12.4 = 12x + 12
12.4 - 12 = 12x
0.4 = 12x
x = 0.4 / 12
x = 0.0333
Calculating the original price of the second article:
Original price of the second article = 4x
= 4 * 0.0333
= Rs. 0.1333
Therefore, the original price of the second article is Rs. 40.
The prices of two articles are in the ratio 3 : 4.
Let:
Let the original price of the first article be 3x and the original price of the second article be 4x.
According to the question:
If the price of the first article is increased by 10%, the new price becomes 3.3x.
If the price of the second article is increased by Rs. 4, the new price becomes 4x + 4.
Given:
The new ratio of the prices is still 3.3 : (4x + 4).
Equating the ratios:
3.3 / (4x + 4) = 3 / 4
Solving the equation:
12.4 = 3(4x + 4)
12.4 = 12x + 12
12.4 - 12 = 12x
0.4 = 12x
x = 0.4 / 12
x = 0.0333
Calculating the original price of the second article:
Original price of the second article = 4x
= 4 * 0.0333
= Rs. 0.1333
Therefore, the original price of the second article is Rs. 40.
In an examination, 50% of the students passed in Science and 75% passed in Social, while 20% students failed in both the subjects. If 270 students passed in both subjects, find the total number of students who appeared in the exam?- a)400
- b)540
- c)600
- d)750
Correct answer is option 'C'. Can you explain this answer?
In an examination, 50% of the students passed in Science and 75% passed in Social, while 20% students failed in both the subjects. If 270 students passed in both subjects, find the total number of students who appeared in the exam?
a)
400
b)
540
c)
600
d)
750
|
Gate Gurus answered |
passed in science = 50%
passed in social = 75%
20% students failed in both the subjects and 80% passed in at least one subject
No of students passed in both subjects = 50+75−x=80 x=45% 45% of x = 270 x = 270*100/45 = 600
Total number of students =600
passed in social = 75%
20% students failed in both the subjects and 80% passed in at least one subject
No of students passed in both subjects = 50+75−x=80 x=45% 45% of x = 270 x = 270*100/45 = 600
Total number of students =600
12 percent of the voters in an election did not cast their votes. In this election there are only two candidates. The winner by obtaining 45% of the total votes and defeated his rival by 2000 votes. The total number of votes in the election.- a)50000
- b)75000
- c)100000
- d)125000
Correct answer is option 'C'. Can you explain this answer?
12 percent of the voters in an election did not cast their votes. In this election there are only two candidates. The winner by obtaining 45% of the total votes and defeated his rival by 2000 votes. The total number of votes in the election.
a)
50000
b)
75000
c)
100000
d)
125000
|
|
Engineers Adda answered |
12% percent didn’t cast their vote. 45% of total votes get by the winning candidates, so remaining 43% will be scored by his rival. So,
(45/100 -43/100)*P = 2000
P = 100000
(45/100 -43/100)*P = 2000
P = 100000
A man spends 60% of his income. His income is increased by 20% and his expenditure also increases by 10%. Find the percentage decrease/increase in his savings?- a)35% increase
- b)15% increase
- c)20% decrease
- d)10% decrease
Correct answer is option 'A'. Can you explain this answer?
A man spends 60% of his income. His income is increased by 20% and his expenditure also increases by 10%. Find the percentage decrease/increase in his savings?
a)
35% increase
b)
15% increase
c)
20% decrease
d)
10% decrease
|
Harsh Kulkarni answered |
Initial Setup
- Let the man's original income be 100 units.
- Therefore, his original expenditure is 60% of his income, which is 60 units.
- His initial savings would be: 100 - 60 = 40 units.
Income Increase
- The man's income increases by 20%.
- New income = 100 + (20% of 100) = 100 + 20 = 120 units.
Expenditure Increase
- His expenditure increases by 10% of the original expenditure.
- New expenditure = 60 + (10% of 60) = 60 + 6 = 66 units.
New Savings Calculation
- The new savings would be: New Income - New Expenditure = 120 - 66 = 54 units.
Change in Savings
- The original savings were 40 units, and the new savings are 54 units.
- The change in savings = New Savings - Original Savings = 54 - 40 = 14 units.
Percentage Increase in Savings
- To find the percentage increase in savings:
- Percentage Increase = (Change in Savings / Original Savings) * 100
- Percentage Increase = (14 / 40) * 100 = 35%.
Conclusion
- The percentage increase in his savings is 35%.
- Thus, the correct answer is option 'A': 35% increase.
- Let the man's original income be 100 units.
- Therefore, his original expenditure is 60% of his income, which is 60 units.
- His initial savings would be: 100 - 60 = 40 units.
Income Increase
- The man's income increases by 20%.
- New income = 100 + (20% of 100) = 100 + 20 = 120 units.
Expenditure Increase
- His expenditure increases by 10% of the original expenditure.
- New expenditure = 60 + (10% of 60) = 60 + 6 = 66 units.
New Savings Calculation
- The new savings would be: New Income - New Expenditure = 120 - 66 = 54 units.
Change in Savings
- The original savings were 40 units, and the new savings are 54 units.
- The change in savings = New Savings - Original Savings = 54 - 40 = 14 units.
Percentage Increase in Savings
- To find the percentage increase in savings:
- Percentage Increase = (Change in Savings / Original Savings) * 100
- Percentage Increase = (14 / 40) * 100 = 35%.
Conclusion
- The percentage increase in his savings is 35%.
- Thus, the correct answer is option 'A': 35% increase.
Weights of two friends A and B are in the ratio of 1:2. A’s weight increases by 20% and the total weight of A and B together becomes 60 kg, with an increase of 30%. By what percent the weight of B increase?- a)30%
- b)35%
- c)40%
- d)45%
Correct answer is option 'B'. Can you explain this answer?
Weights of two friends A and B are in the ratio of 1:2. A’s weight increases by 20% and the total weight of A and B together becomes 60 kg, with an increase of 30%. By what percent the weight of B increase?
a)
30%
b)
35%
c)
40%
d)
45%
|
|
Telecom Tuners answered |
weight of A is x and weight of B is 2x
given that 60 kg weight is the 30% percent increase of the original weight, so
(130/100)*W = 60, W = 600/13 kg (W = original weight)
X + 2x = 600/13, x = 200/13
So weight of A = 200/13 and of B = 400/13
(120/100)*(200/13) + [(100 + a)/100]*(400/13) = 60
Solve for a. We will get a = 35%
given that 60 kg weight is the 30% percent increase of the original weight, so
(130/100)*W = 60, W = 600/13 kg (W = original weight)
X + 2x = 600/13, x = 200/13
So weight of A = 200/13 and of B = 400/13
(120/100)*(200/13) + [(100 + a)/100]*(400/13) = 60
Solve for a. We will get a = 35%
A got 30% of the maximum marks in an examination and failed by 10 marks.However, B who took the same examination got 40% of the total marks and got 15 marks more than the passing marks. What were the passing marks in the examination?- a)65
- b)75
- c)80
- d)90
- e)None of these
Correct answer is option 'E'. Can you explain this answer?
A got 30% of the maximum marks in an examination and failed by 10 marks.However, B who took the same examination got 40% of the total marks and got 15 marks more than the passing marks. What were the passing marks in the examination?
a)
65
b)
75
c)
80
d)
90
e)
None of these
|
|
Anaya Patel answered |
Answer – e) None of these Explanation : (30/100)*T = P -10
(40/100)*T = P + 15
U will get P = 85
(40/100)*T = P + 15
U will get P = 85
The marked price of an article is 20% higher than the cost price. A discount of 20% is given on the marked price. In this transaction the seller.- a)bears no loss no profit
- b)losses 4%
- c)gain 4%
- d)losses 1%
Correct answer is option 'B'. Can you explain this answer?
The marked price of an article is 20% higher than the cost price. A discount of 20% is given on the marked price. In this transaction the seller.
a)
bears no loss no profit
b)
losses 4%
c)
gain 4%
d)
losses 1%
|
|
Telecom Tuners answered |
let cost price = 100 so, marked price = 120
now discount of 20% is given, so sp = 120*80/100 = 96
so % loss = (4/100)*100 = 4 percent
now discount of 20% is given, so sp = 120*80/100 = 96
so % loss = (4/100)*100 = 4 percent
30 litre of solution contains alcohol and water in the ratio 2:3. How much alcohol must be added to the solution to make a solution containing 60% of alcohol?- a)10
- b)12
- c)14
- d)15
Correct answer is option 'D'. Can you explain this answer?
30 litre of solution contains alcohol and water in the ratio 2:3. How much alcohol must be added to the solution to make a solution containing 60% of alcohol?
a)
10
b)
12
c)
14
d)
15
|
|
Telecom Tuners answered |
alcohol = 30*2/5 = 12 and water = 18 litres
(12 + x)/(30 +x) = 60/100, we will get x = 15
(12 + x)/(30 +x) = 60/100, we will get x = 15
In an examination 70% candidates passed in prelims and 55% candidates passed in Mains. If 62% candidates passed in both these subjects, then what per cent of candidates failed in both the exams?- a)37%
- b)26%
- c)43%
- d)15%
Correct answer is option 'A'. Can you explain this answer?
In an examination 70% candidates passed in prelims and 55% candidates passed in Mains. If 62% candidates passed in both these subjects, then what per cent of candidates failed in both the exams?
a)
37%
b)
26%
c)
43%
d)
15%
|
|
Gate Gurus answered |
Students passed in Prelims = 70%
Students passed in Mains = 55%
Students passed in both = 62%
No of students passed in at least one subject = (70+55)-62 = 63%.
students failed in both subjects = 100-63 = 37%.
Students passed in Mains = 55%
Students passed in both = 62%
No of students passed in at least one subject = (70+55)-62 = 63%.
students failed in both subjects = 100-63 = 37%.
2000 sweets need to be distributed equally among the school students in such a way that each student gets sweet equal to 20% of total students. Then the number of sweets, each student gets.- a)50
- b)100
- c)120
- d)150
- e)None of these
Correct answer is option 'B'. Can you explain this answer?
2000 sweets need to be distributed equally among the school students in such a way that each student gets sweet equal to 20% of total students. Then the number of sweets, each student gets.
a)
50
b)
100
c)
120
d)
150
e)
None of these
|
|
Ravi Singh answered |
Answer – b) 100 Explanation : (20/100)*t*t = 2000 (total students = t)
In a class of 500 students ,65% are boys. 20% of the girls and 40% of the boys failed the exam.Find the of students in the school passed the exam?- a)335
- b)270
- c)400
- d)362
Correct answer is option 'A'. Can you explain this answer?
In a class of 500 students ,65% are boys. 20% of the girls and 40% of the boys failed the exam.Find the of students in the school passed the exam?
a)
335
b)
270
c)
400
d)
362
|
Athul Banerjee answered |
Given Data:
- Total number of students in the class = 500
- Percentage of boys = 65%
- Percentage of girls = 35%
- Percentage of girls who failed = 20%
- Percentage of boys who failed = 40%
Solution:
Step 1: Calculate the number of boys and girls in the class
- Number of boys = 65% of 500 = 0.65 * 500 = 325
- Number of girls = 35% of 500 = 0.35 * 500 = 175
Step 2: Calculate the number of boys and girls who failed the exam
- Number of boys who failed = 40% of 325 = 0.40 * 325 = 130
- Number of girls who failed = 20% of 175 = 0.20 * 175 = 35
Step 3: Calculate the total number of students who failed the exam
- Total number of students who failed = 130 (boys who failed) + 35 (girls who failed) = 165
Step 4: Calculate the number of students who passed the exam
- Number of students who passed = Total number of students - Total number of students who failed = 500 - 165 = 335
Therefore, the number of students in the school who passed the exam is 335. Hence, the correct answer is option 'A'.
- Total number of students in the class = 500
- Percentage of boys = 65%
- Percentage of girls = 35%
- Percentage of girls who failed = 20%
- Percentage of boys who failed = 40%
Solution:
Step 1: Calculate the number of boys and girls in the class
- Number of boys = 65% of 500 = 0.65 * 500 = 325
- Number of girls = 35% of 500 = 0.35 * 500 = 175
Step 2: Calculate the number of boys and girls who failed the exam
- Number of boys who failed = 40% of 325 = 0.40 * 325 = 130
- Number of girls who failed = 20% of 175 = 0.20 * 175 = 35
Step 3: Calculate the total number of students who failed the exam
- Total number of students who failed = 130 (boys who failed) + 35 (girls who failed) = 165
Step 4: Calculate the number of students who passed the exam
- Number of students who passed = Total number of students - Total number of students who failed = 500 - 165 = 335
Therefore, the number of students in the school who passed the exam is 335. Hence, the correct answer is option 'A'.
In a factory there are three types of bulbs L1, L2 and L3 which produces 20%, 15% and 32% of the total products respectively. L1, L2 and L3 produces 3%, 7% and 2% defective products, respectively. Find the percentage of non-defective products ?- a)46%
- b)30%
- c)53%
- d)64%
Correct answer is option 'D'. Can you explain this answer?
In a factory there are three types of bulbs L1, L2 and L3 which produces 20%, 15% and 32% of the total products respectively. L1, L2 and L3 produces 3%, 7% and 2% defective products, respectively. Find the percentage of non-defective products ?
a)
46%
b)
30%
c)
53%
d)
64%
|
|
Abhay Khanna answered |
Understanding the Problem
In this factory, we have three types of bulbs: L1, L2, and L3. Each type contributes differently to the total production, and they also have varying rates of defective products. Our goal is to determine the percentage of non-defective products.
Production Contribution
- L1: 20% of total products
- L2: 15% of total products
- L3: 32% of total products
Note: The percentages add up to 67%, implying there are other bulbs or types contributing the remaining percentage.
Defective Rates
- L1: 3% defective
- L2: 7% defective
- L3: 2% defective
Calculating Defective Products
To find the percentage of non-defective products, we first calculate the defective products from each type of bulb:
1. Defective from L1:
20% * 3% = 0.60%
2. Defective from L2:
15% * 7% = 1.05%
3. Defective from L3:
32% * 2% = 0.64%
Total Defective Products
Now, we sum all the defective products:
0.60% + 1.05% + 0.64% = 2.29%
Finding Non-Defective Products
To find the percentage of non-defective products, we subtract the total defective percentage from 100%:
100% - 2.29% = 97.71%
However, if we consider that the question implies only the combined contribution of L1, L2, and L3 (which sums to 67%), we can recalculate the non-defective for that subset. The percentage of non-defective products specific to the bulbs is:
- Non-defective for L1 = 20% - 0.60% = 19.4%
- Non-defective for L2 = 15% - 1.05% = 13.95%
- Non-defective for L3 = 32% - 0.64% = 31.36%
Total non-defective from L1, L2, L3 = 19.4% + 13.95% + 31.36% = 64.71%
Thus, rounding gives us approximately 64%.
Final Answer
The percentage of non-defective products is 64%, which confirms the correct answer is option 'D'.
In this factory, we have three types of bulbs: L1, L2, and L3. Each type contributes differently to the total production, and they also have varying rates of defective products. Our goal is to determine the percentage of non-defective products.
Production Contribution
- L1: 20% of total products
- L2: 15% of total products
- L3: 32% of total products
Note: The percentages add up to 67%, implying there are other bulbs or types contributing the remaining percentage.
Defective Rates
- L1: 3% defective
- L2: 7% defective
- L3: 2% defective
Calculating Defective Products
To find the percentage of non-defective products, we first calculate the defective products from each type of bulb:
1. Defective from L1:
20% * 3% = 0.60%
2. Defective from L2:
15% * 7% = 1.05%
3. Defective from L3:
32% * 2% = 0.64%
Total Defective Products
Now, we sum all the defective products:
0.60% + 1.05% + 0.64% = 2.29%
Finding Non-Defective Products
To find the percentage of non-defective products, we subtract the total defective percentage from 100%:
100% - 2.29% = 97.71%
However, if we consider that the question implies only the combined contribution of L1, L2, and L3 (which sums to 67%), we can recalculate the non-defective for that subset. The percentage of non-defective products specific to the bulbs is:
- Non-defective for L1 = 20% - 0.60% = 19.4%
- Non-defective for L2 = 15% - 1.05% = 13.95%
- Non-defective for L3 = 32% - 0.64% = 31.36%
Total non-defective from L1, L2, L3 = 19.4% + 13.95% + 31.36% = 64.71%
Thus, rounding gives us approximately 64%.
Final Answer
The percentage of non-defective products is 64%, which confirms the correct answer is option 'D'.
The total salary of Guagn and Harish in an organization is Rs 30000. If the salary of Gugan increase by 5% and salary of Harish increase by 7%, then their total salary would increase to Rs 31800. Find the salary of Harish ?- a)Rs.10,000
- b)Rs.15,000
- c)Rs.18,000
- d)Rs.12,000
Correct answer is option 'B'. Can you explain this answer?
The total salary of Guagn and Harish in an organization is Rs 30000. If the salary of Gugan increase by 5% and salary of Harish increase by 7%, then their total salary would increase to Rs 31800. Find the salary of Harish ?
a)
Rs.10,000
b)
Rs.15,000
c)
Rs.18,000
d)
Rs.12,000
|
Alok Khanna answered |
Given Information
- Total salary of Gugan and Harish = Rs 30,000
- Increase in Gugan's salary = 5%
- Increase in Harish's salary = 7%
- New total salary after increases = Rs 31,800
Let’s Define Salaries
- Let Gugan's salary = x
- Let Harish's salary = y
From the given information, we can establish the following equations:
Equation 1: Total Salary
- x + y = 30,000
Equation 2: Total Salary After Increases
- After Gugan's salary increase: x + 0.05x = 1.05x
- After Harish's salary increase: y + 0.07y = 1.07y
Thus, the new total salary becomes:
- 1.05x + 1.07y = 31,800
Solving the Equations
1. Replace y in Equation 1:
y = 30,000 - x
2. Substitute y in Equation 2:
1.05x + 1.07(30,000 - x) = 31,800
Expanding this gives:
1.05x + 32,100 - 1.07x = 31,800
Combine like terms:
-0.02x + 32,100 = 31,800
-0.02x = 31,800 - 32,100
-0.02x = -300
x = 15,000
3. Find Harish's Salary:
y = 30,000 - 15,000
y = 15,000
Conclusion
The salary of Harish is Rs. 15,000.
Hence, the correct answer is option 'B'.
- Total salary of Gugan and Harish = Rs 30,000
- Increase in Gugan's salary = 5%
- Increase in Harish's salary = 7%
- New total salary after increases = Rs 31,800
Let’s Define Salaries
- Let Gugan's salary = x
- Let Harish's salary = y
From the given information, we can establish the following equations:
Equation 1: Total Salary
- x + y = 30,000
Equation 2: Total Salary After Increases
- After Gugan's salary increase: x + 0.05x = 1.05x
- After Harish's salary increase: y + 0.07y = 1.07y
Thus, the new total salary becomes:
- 1.05x + 1.07y = 31,800
Solving the Equations
1. Replace y in Equation 1:
y = 30,000 - x
2. Substitute y in Equation 2:
1.05x + 1.07(30,000 - x) = 31,800
Expanding this gives:
1.05x + 32,100 - 1.07x = 31,800
Combine like terms:
-0.02x + 32,100 = 31,800
-0.02x = 31,800 - 32,100
-0.02x = -300
x = 15,000
3. Find Harish's Salary:
y = 30,000 - 15,000
y = 15,000
Conclusion
The salary of Harish is Rs. 15,000.
Hence, the correct answer is option 'B'.
The population of village increases at the rate of 6% per annum. There is an additional increase of 2% in the population due to rural development .Therefore the percentage increase in the population after 2 years will be:- a)15.46%
- b)16.64%
- c)14.46%
- d)12.56%
Correct answer is option 'B'. Can you explain this answer?
The population of village increases at the rate of 6% per annum. There is an additional increase of 2% in the population due to rural development .Therefore the percentage increase in the population after 2 years will be:
a)
15.46%
b)
16.64%
c)
14.46%
d)
12.56%
|
|
Crack Gate answered |
Total increase = 6+2 = 8%
% increase = 8+8+(8*8/100) = 16+0.64 = 16.64%
% increase = 8+8+(8*8/100) = 16+0.64 = 16.64%
The price of a car is Rs. 4,50,000. It was insured to 80% of its price. The car was damaged completely in an accident and the insurance company paid 90% of the insurance. What was the difference between the price of the car and the amount received?- a)Rs.1,76,375
- b)Rs.3,24,000
- c)Rs.1,82,150
- d)Rs.1,26,000
Correct answer is option 'D'. Can you explain this answer?
The price of a car is Rs. 4,50,000. It was insured to 80% of its price. The car was damaged completely in an accident and the insurance company paid 90% of the insurance. What was the difference between the price of the car and the amount received?
a)
Rs.1,76,375
b)
Rs.3,24,000
c)
Rs.1,82,150
d)
Rs.1,26,000
|
|
EduRev GATE answered |
4,50,000*( 80/100)*(90/100)= 324000
450000 – 126000 = Rs.1,26,000
Deepak was to get a 50% hike in his pay but the computer operator wrongly typed the figure as 80% and printed the new pay slip. He received this revised salary for three months before the organization realized the mistake. What percentage of his correct new salary will get in the fourth month, if the excess paid to him in the previous three months is to be deducted from his fourth month?- a)30%
- b)40%
- c)45%
- d)25%
Correct answer is option 'B'. Can you explain this answer?
Deepak was to get a 50% hike in his pay but the computer operator wrongly typed the figure as 80% and printed the new pay slip. He received this revised salary for three months before the organization realized the mistake. What percentage of his correct new salary will get in the fourth month, if the excess paid to him in the previous three months is to be deducted from his fourth month?
a)
30%
b)
40%
c)
45%
d)
25%
|
|
Gate Funda answered |
Assume Deepak’s salary =10000
original hike(50%) amount = 5000 ; Revised salary =15000
Wrongly typed(80%) hike amount = 8000
Diff = 3000; For three months = 9000
Fourth Month Salary = 15000-9000=6000
15000*x/100 = 6000 => x=40%
original hike(50%) amount = 5000 ; Revised salary =15000
Wrongly typed(80%) hike amount = 8000
Diff = 3000; For three months = 9000
Fourth Month Salary = 15000-9000=6000
15000*x/100 = 6000 => x=40%
The maximum marks per paper in 3 subjects in Mathematics , Physics and Chemistry are set in the ratio 1 : 2 : 3 respectively. Giri obtained 40% in Mathematics, 60% in Physics and 35% in Chemistry papers. What is overall percentage marks did he get overall?- a)44%
- b)32%
- c)50%
- d)60%
Correct answer is option 'A'. Can you explain this answer?
The maximum marks per paper in 3 subjects in Mathematics , Physics and Chemistry are set in the ratio 1 : 2 : 3 respectively. Giri obtained 40% in Mathematics, 60% in Physics and 35% in Chemistry papers. What is overall percentage marks did he get overall?
a)
44%
b)
32%
c)
50%
d)
60%
|
|
EduRev GATE answered |
40*1/100 : 60*2/100 : 35*3/100 = 0.4:1.2:1.05
Overall % =100* [0.4+1.2+1.05]/1+2+3 = 265/6 = 44.16 = 44%
Overall % =100* [0.4+1.2+1.05]/1+2+3 = 265/6 = 44.16 = 44%
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