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All questions of Ratio and Proportion for RRB NTPC/ASM/CA/TA Exam
In a mixture 60 litres, the ratio of milk and water 2 : 1. If this ratio is to be 1 : 2, then the quanity of water to be further added is:- a)20 litres
- b)30 litres
- c)40 litres
- d)60 litres
Correct answer is option 'D'. Can you explain this answer?
In a mixture 60 litres, the ratio of milk and water 2 : 1. If this ratio is to be 1 : 2, then the quanity of water to be further added is:
a)
20 litres
b)
30 litres
c)
40 litres
d)
60 litres
|
Mihir Sen answered |
Quantity of milk 
Quantity of water in it = (60 - 40) litres = 20 litres.
New ratio = 1 : 2
Let quantity of water to be added further be x litres
Then, milk : water
∴ Quantity of water to be added = 60 litres.
Quantity of water in it = (60 - 40) litres = 20 litres.
New ratio = 1 : 2
Let quantity of water to be added further be x litres
Then, milk : water
∴ Quantity of water to be added = 60 litres.
The ratio of the income of A and B is 7 : 8, and the ratio of the income of B and C is 8 : 11, If the difference in the income earned by A and C is Rs. 800, then find the sum of income earned by all three of them.- a)Rs. 5200
- b)Rs. 4800
- c)Rs. 4000
- d)Rs. 3600
Correct answer is option 'A'. Can you explain this answer?
The ratio of the income of A and B is 7 : 8, and the ratio of the income of B and C is 8 : 11, If the difference in the income earned by A and C is Rs. 800, then find the sum of income earned by all three of them.
a)
Rs. 5200
b)
Rs. 4800
c)
Rs. 4000
d)
Rs. 3600
|
Kiran Reddy answered |
Given:
The ratio of the income of A and B = 7 : 8
The ratio of the income of B and C = 8 : 11
The difference in the income earned by A and C = Rs. 800
Calculation:
According to the question,
The ratio of the income of A and B = 7 : 8
The ratio of the income of B and C = 8 : 11
By combining the ratios, we get,
The ratio of the income of A, B and C = 7 : 8 : 11
Income of C = 11k
Income of A = 7k
The difference in the income earned by A and C = 11k - 7k = 4k
Again according to the question,
⇒ 4k = 800
⇒ k = 200
The income of A, B and C = 7k + 8k + 11k = 26k
Sum of income of A, B and C = 26 × 200 = Rs. 5200
Therefore, 'Rs. 5200' is the required answer.
Can you explain the answer of this question below:According to the Boyle’s law, at a constant temperature, pressure of a definite mass of gas is inversely proportional to the volume. If the pressure is reduced by 20%, find the respective change in volume.
- A:
-33.33%
- B:
+25%
- C:
-25%
- D:
+33.33%
The answer is b.
According to the Boyle’s law, at a constant temperature, pressure of a definite mass of gas is inversely proportional to the volume. If the pressure is reduced by 20%, find the respective change in volume.
-33.33%
+25%
-25%
+33.33%
|
Ishan Chaudhary answered |
Point mutation involves- a)Change in single base pair
- b)Deletion
- c)Insertion
- d)Duplication
Correct answer is option 'A'. Can you explain this answer?
Point mutation involves
a)
Change in single base pair
b)
Deletion
c)
Insertion
d)
Duplication
|
Honey answered |
Yes. it involves point mutation as in sickle call anaemia.
Seats for Mathematics, Physics and Biology in a school are in the ratio 5 : 7 : 8. There is a proposal to increase these seats by 40%, 50% and 75% respectively. What will be the ratio after increased seats?- a)2 : 3 : 4
- b)6 : 7 : 8
- c)6 : 8 : 9
- d)None of these
Correct answer is option 'A'. Can you explain this answer?
Seats for Mathematics, Physics and Biology in a school are in the ratio 5 : 7 : 8. There is a proposal to increase these seats by 40%, 50% and 75% respectively. What will be the ratio after increased seats?
a)
2 : 3 : 4
b)
6 : 7 : 8
c)
6 : 8 : 9
d)
None of these
|
Future Foundation Institute answered |
Let the incomes be 4x, 5x, 6x and the spending be 6y, 7y, 8y and savings are (4x–6y), (5x–7y) & (6x–8y)
Sheldon saves 1/4th of his income.
Sheldon saves 1/4th of his income.
Therefore:
⇒ 4x – 6y = 4x / 4
⇒ 4x – 6y = x
⇒ 3x = 6y
⇒ x / y = 2
∴ y = x / 2
⇒ 4x – 6y = x
⇒ 3x = 6y
⇒ x / y = 2
∴ y = x / 2
Ratio of Sheldon’s Leonard’s & Howard’s savings:
= 4x – 6y : 5x – 7y : 6x – 8y
= x : 5x – 7y : 6x – 8y
= x : 5x – 7x / 2 : 6x – 8x / 2
= x : 3x / 2 : 2x
= 2 : 3 : 4
= x : 5x – 7y : 6x – 8y
= x : 5x – 7x / 2 : 6x – 8x / 2
= x : 3x / 2 : 2x
= 2 : 3 : 4
A and B together have Rs. 1210. If 
of A's amount is equal to 
of B's amount, how much amount does B have?
- a)Rs. 460
- b)Rs. 484
- c)Rs. 550
- d)Rs. 664
Correct answer is 'B'. Can you explain this answer?
A and B together have Rs. 1210. If of A's amount is equal to of B's amount, how much amount does B have?
of A's amount is equal to of B's amount, how much amount does B have?a)
Rs. 460
b)
Rs. 484
c)
Rs. 550
d)
Rs. 664
|
Manoj Ghosh answered |
A+B=1210(4/15)A=(2/5)B2A=3BTherefore, A=(3B)/2and substituting, (3B/2)+B=1210and hence, 5B=2420 => B=484 Rs.
The annual income of Victor and Angela are in the ratio 8 : 3 and their annual expenditures are in the ratio 4 : 1. If each save Rs. 2000 per annum. What is the annual expense of Angela?a)2000b)4000c)5000d)2500Correct answer is option 'D'. Can you explain this answer?
|
Aisha Gupta answered |
► If new values of x, y, z are x′, y′ and z′, and respectively then x′ : y′ = 4 : 5, y′ : z′ = 3 : 4
⇒ x′ : y′ : z′ = 12 : 15 : 20
⇒ x + y + z = 5000
⇒ x′ + 50 + y′ + 100 + z′ + 150 = 5000 x′ + y′ + z′ = 4700
⇒ 12k + 15k + 20k = 4700 k = 100
⇒ x + y + z = 5000
⇒ x′ + 50 + y′ + 100 + z′ + 150 = 5000 x′ + y′ + z′ = 4700
⇒ 12k + 15k + 20k = 4700 k = 100
► x = 1200 + 50 = 1250
► y = 1500 + 100 = 1600 z = 2000 + 150 = 2150
► x + y = 1250 + 1600 = 2850
► y = 1500 + 100 = 1600 z = 2000 + 150 = 2150
► x + y = 1250 + 1600 = 2850
Arun has a certain amount of money in the denomination of 1 rupee and 10 rupee notes . T he number of 1 rupee notes multiplied by the number of 10 rupee notes is equal to the total money (in rupees) that he has. What is the total number of ten rupee notes that he can have?- a)11
- b)13
- c)15
- d)None of these
Correct answer is option 'D'. Can you explain this answer?
Arun has a certain amount of money in the denomination of 1 rupee and 10 rupee notes . T he number of 1 rupee notes multiplied by the number of 10 rupee notes is equal to the total money (in rupees) that he has. What is the total number of ten rupee notes that he can have?
a)
11
b)
13
c)
15
d)
None of these
|
Dhruv Verma answered |
Let x = no. of Re 1 notes and y = no. of Rs 10 notes So, xy = x+ 10y ⇒xy = x + 10y Now, go through options
Two-fifth of Anil’s salary is equal of Bhuvan’s salary and seven -ninth of Bhuvan’s salary is equal to Chandra’s salary. The sum of the salary of all of them is Rs 770. Which of the following is the salary of each?- a)300, 225, 250
- b)500, 425, 375
- c)450, 180, 140
- d)520, 610, 475
Correct answer is option 'C'. Can you explain this answer?
Two-fifth of Anil’s salary is equal of Bhuvan’s salary and seven -ninth of Bhuvan’s salary is equal to Chandra’s salary. The sum of the salary of all of them is Rs 770. Which of the following is the salary of each?
a)
300, 225, 250
b)
500, 425, 375
c)
450, 180, 140
d)
520, 610, 475
|
|
Anaya Patel answered |
A metal trader buys 2 kinds of silver foils, the ratio of their prices being 1:4. He sells the alloy at Rs 90 per kg so that he can make a profit of 20%. If the ratio of their quantities present in a alloy is 6:1 respectively, find the purchase price of the foil present in lesser quantity.
- a)Rs 52.5
- b)Rs 55
- c)Rs 47.5
- d)Rs 45
Correct answer is option 'A'. Can you explain this answer?
A metal trader buys 2 kinds of silver foils, the ratio of their prices being 1:4. He sells the alloy at Rs 90 per kg so that he can make a profit of 20%. If the ratio of their quantities present in a alloy is 6:1 respectively, find the purchase price of the foil present in lesser quantity.
a)
Rs 52.5
b)
Rs 55
c)
Rs 47.5
d)
Rs 45
|
Arya Roy answered |
CP = 75
Anand and Bhavana have a few one rupee, 50 paise and 25 paise coins each. The total amount with each of them is Rs 5. The number of coins of two of the three types of coins that Anand has are equal and same is the case for the coins that Bhavana has. If Anand has the maximum possible total number of coins, then find the maximum possible total number of coins that Bhavana can have given that she has fewer coins than Anand.- a)16
- b)12
- c)10
- d)9
Correct answer is option 'B'. Can you explain this answer?
Anand and Bhavana have a few one rupee, 50 paise and 25 paise coins each. The total amount with each of them is Rs 5. The number of coins of two of the three types of coins that Anand has are equal and same is the case for the coins that Bhavana has. If Anand has the maximum possible total number of coins, then find the maximum possible total number of coins that Bhavana can have given that she has fewer coins than Anand.
a)
16
b)
12
c)
10
d)
9
|
Nandita Kaur answered |
Village-chief contribution = Rs 1.2 lakhs, so villagers’ contribution = Rs 1.2 lakhs Now, Go through the options.
In a bag, there are coins of 25 p, 10 p and 5 p in the ratio of 1 : 2 : 3. If there is Rs. 30 in all, how many 5 p coins are there?- a)50
- b)100
- c)150
- d)200
Correct answer is option 'C'. Can you explain this answer?
In a bag, there are coins of 25 p, 10 p and 5 p in the ratio of 1 : 2 : 3. If there is Rs. 30 in all, how many 5 p coins are there?
a)
50
b)
100
c)
150
d)
200
|
Gowri Chakraborty answered |
Let x is the number of 25 paisa coins then 2x and 3x will be for 10 and 5 paisa coins.
Now 30 rupees equal to 30*100 paisa now total paisa equal to x*25+2x*10+3x*5=3000.
60x = 3000.
x = 50.
Now number 5 paisa coin is 3x equal to 3*50 = 150.
Can you explain the answer of this question below:The difference between the two positive numbers is 10 and the ratio between them is 5:3. Find the product of the two numbers.
- A:
375
- B:
325
- C:
275
- D:
125
The answer is a.
The difference between the two positive numbers is 10 and the ratio between them is 5:3. Find the product of the two numbers.
375
325
275
125
|
Subham Basu answered |
Let the nos. be 5x and 3x. then, 5x - 3x = 10 2x = 10, x = 5 Required product = 5x x 3x = 5 x 5 x 3 x 5 = 375
An alloy of manganese, tin and bronze contains 90% bronze, 7% manganese and 3% tin. A second alloy of bronze and tin is melted with the first and the mixture contains 85% of bronze, 5% of manganese and 10% of tin. What is the percentage of bronze in the second alloy?- a)67.5%
- b)72.5%
- c)77.5%
- d)82.5%
Correct answer is 'B'. Can you explain this answer?
An alloy of manganese, tin and bronze contains 90% bronze, 7% manganese and 3% tin. A second alloy of bronze and tin is melted with the first and the mixture contains 85% of bronze, 5% of manganese and 10% of tin. What is the percentage of bronze in the second alloy?
a)
67.5%
b)
72.5%
c)
77.5%
d)
82.5%
|
Sameer Rane answered |
Say M and N are the total volumes of first and second alloys respectively.
Say C, Z and T represent Copper, Tin and Zinc percentages respectively in second alloy.
⇒ C + Z + T = 100 …… Eq.1
Amount of copper in the mixture = 0.90M + (C/100) x N = 0.85 x (M + N)
⇒ 0.05M = (0.85 – C/100) x N
⇒ C = 85 – 5 x (M/N) ….. Eq.2
Amount of Zinc in the mixture = 0.07M + (Z/100) x N = 0.05 x (M + N)
⇒ 0.02M = (0.05 – Z/100) x N
⇒ Z = 5 – 2 x (M/N) ….. Eq.3
Amount of copper in the mixture = 0.03M + (T/100) x N = 0.10 x (M + N)
⇒ –0.07M = (0.10 – T/100) x N
⇒ T = 10 + 7 x (M/N) …… Eq.4
Given Zinc percent in second alloy is Zero
⇒ Z = 0
Eq.3 ⇒ 0 = 5 – 2 x (M/N)
⇒ M/N = 5/2
Substitute M/N = 5/2 in Eq.4
⇒ T = 10 + 7 x (5/2) = 10 + 17.5 = 27.5%
∴ Tin in second alloy = 27.5%
11 : b : 44 are in continued proportion. Find b.- a)4
- b)22
- c)44
- d)11
Correct answer is option 'B'. Can you explain this answer?
11 : b : 44 are in continued proportion. Find b.
a)
4
b)
22
c)
44
d)
11
|
|
Alok Verma answered |
We know that if a, b and c are in continued proportion then b2 = ac
b2 = 11.44
b2 = 484
b = 22
b2 = 11.44
b2 = 484
b = 22
The salaries A, B, C are in the ratio 2 : 3 : 5. If the increments of 15%, 10% and 20% are allowed respectively in their salaries, then what will be new ratio of their salaries?- a)3 : 3 : 10
- b)10 : 11 : 20
- c)23 : 33 : 60
- d)Cannot be determined
Correct answer is option 'C'. Can you explain this answer?
The salaries A, B, C are in the ratio 2 : 3 : 5. If the increments of 15%, 10% and 20% are allowed respectively in their salaries, then what will be new ratio of their salaries?
a)
3 : 3 : 10
b)
10 : 11 : 20
c)
23 : 33 : 60
d)
Cannot be determined
|
|
Kavya Saxena answered |
Find the ratio A : B : C : D : E if,
A : B = 4 : 5
B : C = 6 : 7
C : D = 9 : 10
D : E = 5 : 2- a)200 : 270 : 315 : 350 : 140
- b)120 : 270 : 315 : 350 : 140
- c) 216 : 270 : 315 : 350 : 140
- d)216 : 270 : 315 : 350 : 210
Correct answer is option 'C'. Can you explain this answer?
Find the ratio A : B : C : D : E if,
A : B = 4 : 5
B : C = 6 : 7
C : D = 9 : 10
D : E = 5 : 2
A : B = 4 : 5
B : C = 6 : 7
C : D = 9 : 10
D : E = 5 : 2
a)
200 : 270 : 315 : 350 : 140
b)
120 : 270 : 315 : 350 : 140
c)
216 : 270 : 315 : 350 : 140
d)
216 : 270 : 315 : 350 : 210
|
|
Rhea Reddy answered |
A : B = 4 : 5
B : C = 6 : 7
C : D = 9 : 10
D : E = 5 : 2
A : B : C : D : E = 4 x 6 x 9 x 5 : 5 x 6 x 9 x 5: 5 x 7 x 9 x 5: 5 x 7 x 10 x 5: 5 x 7 x 10 x 2
216 : 270 : 315 : 350 : 140
The required ratio A : B : C : D : E is 216 : 270 : 315 : 350 : 140
B : C = 6 : 7
C : D = 9 : 10
D : E = 5 : 2
A : B : C : D : E = 4 x 6 x 9 x 5 : 5 x 6 x 9 x 5: 5 x 7 x 9 x 5: 5 x 7 x 10 x 5: 5 x 7 x 10 x 2
216 : 270 : 315 : 350 : 140
The required ratio A : B : C : D : E is 216 : 270 : 315 : 350 : 140
Can you explain the answer of this question below:A and B invest Rs 12,000 and Rs 16,000 respectively in a business. At the year-end, they share the profit in the ratio of 3:1. If A has invested his capital for the whole year, for how many months B has invested his capital?
- A:
4 months
- B:
3 months
- C:
6 months
- D:
8 months
The answer is b.
A and B invest Rs 12,000 and Rs 16,000 respectively in a business. At the year-end, they share the profit in the ratio of 3:1. If A has invested his capital for the whole year, for how many months B has invested his capital?
4 months
3 months
6 months
8 months
|
Saranya Kaur answered |
Let B invested for n months
n = 3
Gandhiji owns cows, some black and some white. He finds that 4 black cows and 3 white cows gave the same amount of milk in 5 days as 3 black cows and 5 white cows gave in 4 days. What is the ratio of milk given by a black cow in a day to that given by a white cow in a day?- a)8 : 5
- b)5 : 8
- c)3 : 5
- d)5 : 3
Correct answer is option 'B'. Can you explain this answer?
Gandhiji owns cows, some black and some white. He finds that 4 black cows and 3 white cows gave the same amount of milk in 5 days as 3 black cows and 5 white cows gave in 4 days. What is the ratio of milk given by a black cow in a day to that given by a white cow in a day?
a)
8 : 5
b)
5 : 8
c)
3 : 5
d)
5 : 3
|
Janhavi Nambiar answered |
Let 1 black cow gives x litres milk in 1 day and 1 white cow gives y litres milk in 1 day. Then 5(4.x + 3y) = 4(3x + 5y) ⇒ 20x + 15y = 12x + 20y
If 4 : 8 : C are in continued proportion then find C?- a)16
- b)4
- c)36
- d)34
Correct answer is option 'A'. Can you explain this answer?
If 4 : 8 : C are in continued proportion then find C?
a)
16
b)
4
c)
36
d)
34
|
|
Aarav Sharma answered |
We know that if a, b and c are in continued proportion,
then b2 = ac
82 = 4.C
C = 64/4 = 16
then b2 = ac
82 = 4.C
C = 64/4 = 16
Can you explain the answer of this question below:Two number are in the ratio 3 : 5. If 9 is subtracted from each, the new numbers are in the ratio 12 : 23. The smaller number is:
- A:
27
- B:
33
- C:
49
- D:
55
The answer is B.
Two number are in the ratio 3 : 5. If 9 is subtracted from each, the new numbers are in the ratio 12 : 23. The smaller number is:
27
33
49
55
|
Sagar Sharma answered |
Given:
The ratio of two numbers is 3:5
After subtracting 9 from each number, the new ratio is 12:23
Let's assume the two numbers in the original ratio are 3x and 5x.
Ratio of the new numbers:
(3x-9) : (5x-9) = 12 : 23
Cross-multiplying, we get:
12(5x-9) = 23(3x-9)
Simplifying the equation:
60x - 108 = 69x - 207
-9x = -99
x = 11
Finding the smaller number:
Smaller number = 3x = 3 * 11 = 33
Therefore, the smaller number is 33, which corresponds to option 'B'.
The ratio of two numbers is 3:5
After subtracting 9 from each number, the new ratio is 12:23
Let's assume the two numbers in the original ratio are 3x and 5x.
Ratio of the new numbers:
(3x-9) : (5x-9) = 12 : 23
Cross-multiplying, we get:
12(5x-9) = 23(3x-9)
Simplifying the equation:
60x - 108 = 69x - 207
-9x = -99
x = 11
Finding the smaller number:
Smaller number = 3x = 3 * 11 = 33
Therefore, the smaller number is 33, which corresponds to option 'B'.
A sum of Rs. 12,384 is divided between A, B, C and D such that the ratio of the shares of A and B is 3 : 4, that of B and C is 5 : 6, and that of C and D is 8 : 9. What is the share of C ? - a)Rs. 2,880
- b)Rs. 3,888
- c)Rs. 3,456
- d)Rs. 2,160
Correct answer is option 'C'. Can you explain this answer?
A sum of Rs. 12,384 is divided between A, B, C and D such that the ratio of the shares of A and B is 3 : 4, that of B and C is 5 : 6, and that of C and D is 8 : 9. What is the share of C ?
a)
Rs. 2,880
b)
Rs. 3,888
c)
Rs. 3,456
d)
Rs. 2,160
|
Shilpa Choudhury answered |
Given:
A : B = 3 : 4
B : C = 5 : 6
C : D = 8 : 9
Sum to divided among them = Rs. 12,384
Concept used:
Ratio Proportion
Calculation:
A : B = 3 : 4 = 15 : 20
B : C = 5 : 6 = 20 : 24
C : D = 8 : 9 = 24 : 27
A : B : C : D = 15 : 20 : 24 : 27
Share of C = 24/(15 + 20 + 24 + 27) × 12384 = Rs. 3456
∴ The share of C is Rs. 3456.
Bidhan is planning to buy a bike worth Rs 35,000, provided his brother agrees to lend him 3/2 times the money. Bidhan contributes and the financer provides 3 times the brother’s contribution. How much does Bidhan’s brother contribute?- a)5,000
- b)7,500
- c)10,000
- d)7,000
Correct answer is option 'B'. Can you explain this answer?
Bidhan is planning to buy a bike worth Rs 35,000, provided his brother agrees to lend him 3/2 times the money. Bidhan contributes and the financer provides 3 times the brother’s contribution. How much does Bidhan’s brother contribute?
a)
5,000
b)
7,500
c)
10,000
d)
7,000
|
|
Nikita Singh answered |
The sum of the ages of the 4 members of Sinha family is 140 years. 5 years ago the ages of the 4 members Nishu, Vicky, Mrs Sinha and Mr Sinha were in the ratio of 2 : 3 : 7 : 8 . After how many years would Nishu be as old as the present age of his mother?- a)10yrs
- b)17yrs
- c)30 yrs
- d)32 yrs
Correct answer is option 'C'. Can you explain this answer?
The sum of the ages of the 4 members of Sinha family is 140 years. 5 years ago the ages of the 4 members Nishu, Vicky, Mrs Sinha and Mr Sinha were in the ratio of 2 : 3 : 7 : 8 . After how many years would Nishu be as old as the present age of his mother?
a)
10yrs
b)
17yrs
c)
30 yrs
d)
32 yrs
|
Lavanya Menon answered |
The monthly incomes of X and Y are in the ratio of 4:3 and their monthly expenses are in the ratio of 3:2. However, each saves Rs. 6,000 per month. What is their total monthly income?
- a)Rs. 28,000
- b)Rs. 42,000
- c)Rs. 56,000
- d)Rs. 84,000
Correct answer is option 'B'. Can you explain this answer?
The monthly incomes of X and Y are in the ratio of 4:3 and their monthly expenses are in the ratio of 3:2. However, each saves Rs. 6,000 per month. What is their total monthly income?
a)
Rs. 28,000
b)
Rs. 42,000
c)
Rs. 56,000
d)
Rs. 84,000
|
|
Kishan Darak answered |
Since expenses and Savings are correlated
Therefore income of:
X=6000×4=24000
Y=6000×3=18000
x+y =24000+18000=42000(that is option 'B' is the right answer
Therefore income of:
X=6000×4=24000
Y=6000×3=18000
x+y =24000+18000=42000(that is option 'B' is the right answer
In a library, the ratio of number of story books to that of non-story books was 4:3 and total number of story books was 1248. When some more story books were bought, the ratio became 5:3. Find the number of story books bought.- a) 312
- b) 321
- c) 936
- d) 1560
Correct answer is option 'A'. Can you explain this answer?
In a library, the ratio of number of story books to that of non-story books was 4:3 and total number of story books was 1248. When some more story books were bought, the ratio became 5:3. Find the number of story books bought.
a)
312
b)
321
c)
936
d)
1560
|
Ashwini Chatterjee answered |
**Given information:**
- The ratio of the number of story books to that of non-story books was 4:3.
- The total number of story books was 1248.
- When some more story books were bought, the ratio became 5:3.
**Let's solve the problem step by step:**
**Step 1: Calculate the number of non-story books**
- Since the ratio of story books to non-story books is 4:3, let's assume the number of story books as 4x and the number of non-story books as 3x.
- According to the given information, the total number of story books is 1248. So, we can write the equation as 4x = 1248.
- Solving the equation, we get x = 1248/4 = 312.
- Therefore, the number of non-story books is 3x = 3 * 312 = 936.
**Step 2: Calculate the number of story books after the purchase**
- After some more story books were bought, the ratio became 5:3. Let's assume the number of additional story books as y.
- Now, the total number of story books is 1248 + y, and the total number of non-story books is still 936.
- According to the new ratio, the equation can be written as (1248 + y)/936 = 5/3.
- Cross-multiplying, we get 3 * (1248 + y) = 5 * 936.
- Simplifying the equation, we have 3744 + 3y = 4680.
- Subtracting 3744 from both sides, we get 3y = 936.
- Dividing both sides by 3, we get y = 936/3 = 312.
**Step 3: Calculate the number of story books bought**
- The number of story books bought is given by the value of y, which we calculated as 312.
Therefore, the number of story books bought is 312.
Hence, the correct answer is option A) 312.
- The ratio of the number of story books to that of non-story books was 4:3.
- The total number of story books was 1248.
- When some more story books were bought, the ratio became 5:3.
**Let's solve the problem step by step:**
**Step 1: Calculate the number of non-story books**
- Since the ratio of story books to non-story books is 4:3, let's assume the number of story books as 4x and the number of non-story books as 3x.
- According to the given information, the total number of story books is 1248. So, we can write the equation as 4x = 1248.
- Solving the equation, we get x = 1248/4 = 312.
- Therefore, the number of non-story books is 3x = 3 * 312 = 936.
**Step 2: Calculate the number of story books after the purchase**
- After some more story books were bought, the ratio became 5:3. Let's assume the number of additional story books as y.
- Now, the total number of story books is 1248 + y, and the total number of non-story books is still 936.
- According to the new ratio, the equation can be written as (1248 + y)/936 = 5/3.
- Cross-multiplying, we get 3 * (1248 + y) = 5 * 936.
- Simplifying the equation, we have 3744 + 3y = 4680.
- Subtracting 3744 from both sides, we get 3y = 936.
- Dividing both sides by 3, we get y = 936/3 = 312.
**Step 3: Calculate the number of story books bought**
- The number of story books bought is given by the value of y, which we calculated as 312.
Therefore, the number of story books bought is 312.
Hence, the correct answer is option A) 312.
The ratio of the number of boys and girls in a college is 7 : 8. If the percentage increase in the number of boys and girls be 20% and 10% respectively, what will be the new ratio?- a)8 : 9
- b)17 : 18
- c)21 : 22
- d)Cannot be determined
Correct answer is option 'C'. Can you explain this answer?
The ratio of the number of boys and girls in a college is 7 : 8. If the percentage increase in the number of boys and girls be 20% and 10% respectively, what will be the new ratio?
a)
8 : 9
b)
17 : 18
c)
21 : 22
d)
Cannot be determined
|
Ravi Singh answered |
The sum of four numbers is 253. The ratio of the first number to the second number is 2:3. The ratio of the second number to the third number is 5:6. The ratio of the third number to the fourth number is 8:9. What is the average of the second number and the third number?- a)72
- b)132
- c)60
- d)66
Correct answer is option 'D'. Can you explain this answer?
The sum of four numbers is 253. The ratio of the first number to the second number is 2:3. The ratio of the second number to the third number is 5:6. The ratio of the third number to the fourth number is 8:9. What is the average of the second number and the third number?
a)
72
b)
132
c)
60
d)
66
|
|
Anaya Patel answered |
Let the 1stno. A = X
2nd no.= B , 3rd no.= C , 4th no. = D
A: B =2:3
A/B = 2/3
x/B =2/3
B= 3x/2
B:C=5:6
(3x/2)/ C= 5/6
C=( 6×3x)/2×5= 9x/5
C= 9x/5
C:D= 8:9
9x/5/ D = 8/9
D= (9x×9)/8×5= 81x/40
D= 81x/40
A+B+C+D= 253. (GIVEN)
x+ 3x/2+9x/5+81x/40
Lcm = 40
(40x+ 60x+ 72x+81x)/40= 253
253x= 253×40
X= (253×40)/253= 40
Ist no.(A)= X= 40
2no.(B)= 3x/2=( 3 × 40)/2= 60
3rd no.(C)= 9x/5 = (9×40)/5= 72
4th no.(D)= 81x/40=( 81×40/)/40= 81
Average of numbers= sum of observations/ total no.of observations
Average of 2nd no. & 3rd no.= (60+72)/2= 132/2= 66
2nd no.= B , 3rd no.= C , 4th no. = D
A: B =2:3
A/B = 2/3
x/B =2/3
B= 3x/2
B:C=5:6
(3x/2)/ C= 5/6
C=( 6×3x)/2×5= 9x/5
C= 9x/5
C:D= 8:9
9x/5/ D = 8/9
D= (9x×9)/8×5= 81x/40
D= 81x/40
A+B+C+D= 253. (GIVEN)
x+ 3x/2+9x/5+81x/40
Lcm = 40
(40x+ 60x+ 72x+81x)/40= 253
253x= 253×40
X= (253×40)/253= 40
Ist no.(A)= X= 40
2no.(B)= 3x/2=( 3 × 40)/2= 60
3rd no.(C)= 9x/5 = (9×40)/5= 72
4th no.(D)= 81x/40=( 81×40/)/40= 81
Average of numbers= sum of observations/ total no.of observations
Average of 2nd no. & 3rd no.= (60+72)/2= 132/2= 66
In a fort there are 1600 soldiers fighting a battle against their enemy. On a particular day after their morning meal the balance provision inside the fort is only sufficient for 12 days at the rate of 1.2 kg per day. If by the evening 400 soldiers die then for how many days will the provision be sufficient for remaining men at the rate of 1.6 kg per day. (Assume soldiers eat either in morning or in evening).- a)10
- b)8
- c)18
- d)12
Correct answer is option 'D'. Can you explain this answer?
In a fort there are 1600 soldiers fighting a battle against their enemy. On a particular day after their morning meal the balance provision inside the fort is only sufficient for 12 days at the rate of 1.2 kg per day. If by the evening 400 soldiers die then for how many days will the provision be sufficient for remaining men at the rate of 1.6 kg per day. (Assume soldiers eat either in morning or in evening).
a)
10
b)
8
c)
18
d)
12
|
|
Alok Verma answered |
Total quantity of food at the beginning of the day
= (1600) (12) (1.2)
Total number of soldiers left at the end of the day 1200
Now we have to calculate that for how long is available provision enough for the left-out soldiers
(1200) (x) (1.6)
(1600) (12) (1.2) = (1200) (x) (1.6)
Solving it for the value of x
We get x = 12
The provision is sufficient for 1200 soldiers for 12 days.
= (1600) (12) (1.2)
Total number of soldiers left at the end of the day 1200
Now we have to calculate that for how long is available provision enough for the left-out soldiers
(1200) (x) (1.6)
(1600) (12) (1.2) = (1200) (x) (1.6)
Solving it for the value of x
We get x = 12
The provision is sufficient for 1200 soldiers for 12 days.
Salaries of Ravi and Sumit are in the ratio 2 : 3. If the 'salary of each' one of them is increased by Rs. 4000, the new ratio becomes 40 : 57. What is Sumit's present salary?
- a)Rs. 17,000
- b)Rs. 20,000
- c)Rs. 25,500
- d)Rs. 38,000
Correct answer is option 'D'. Can you explain this answer?
Salaries of Ravi and Sumit are in the ratio 2 : 3. If the 'salary of each' one of them is increased by Rs. 4000, the new ratio becomes 40 : 57. What is Sumit's present salary?
a)
Rs. 17,000
b)
Rs. 20,000
c)
Rs. 25,500
d)
Rs. 38,000
|
|
Sameer Rane answered |
∴ Sumit's present salary = (3x + 4000) = Rs.(34000 + 4000) = Rs. 38000.
A bag has ₹ 785 in the denomination of ₹ 2, ₹ 5 and ₹ 10 coins. The coins are in the ratio of 6 : 9 : 10. How many coins of ₹ 5 are in the bag?- a)60
- b)12
- c)45
- d)24
Correct answer is option 'C'. Can you explain this answer?
A bag has ₹ 785 in the denomination of ₹ 2, ₹ 5 and ₹ 10 coins. The coins are in the ratio of 6 : 9 : 10. How many coins of ₹ 5 are in the bag?
a)
60
b)
12
c)
45
d)
24
|
|
Anjana Singh answered |
Given:
₹ 785 in the denomination of ₹ 2, ₹ 5 and ₹ 10 coins
The coins are in the ratio of 6 : 9 : 10
Calculation:
Let the number of coins of ₹ 2, ₹ 5 and ₹ 10 be 6x, 9x, and 10x respectively
⇒ (2 × 6x) + (5 × 9x) + (10 × 10x) = 785
⇒ 157x = 785
∴ x = 5
Number of coins of ₹ 5 = 9x = 9 × 5 = 45
∴ 45 coins of ₹ 5 are in the bag
₹ 785 in the denomination of ₹ 2, ₹ 5 and ₹ 10 coins
The coins are in the ratio of 6 : 9 : 10
Calculation:
Let the number of coins of ₹ 2, ₹ 5 and ₹ 10 be 6x, 9x, and 10x respectively
⇒ (2 × 6x) + (5 × 9x) + (10 × 10x) = 785
⇒ 157x = 785
∴ x = 5
Number of coins of ₹ 5 = 9x = 9 × 5 = 45
∴ 45 coins of ₹ 5 are in the bag
In a garrison of 3600 men, the provisions were sufficient for 20 days at the rate of 1.5 kg per man per day. If x more men joined, the provisions would be sufficient for 12 days at the rate of 2 kg per man per day. Find x.- a)600
- b)800
- c)900
- d)720
Correct answer is option 'C'. Can you explain this answer?
In a garrison of 3600 men, the provisions were sufficient for 20 days at the rate of 1.5 kg per man per day. If x more men joined, the provisions would be sufficient for 12 days at the rate of 2 kg per man per day. Find x.
a)
600
b)
800
c)
900
d)
720
|
|
Rhea Reddy answered |
Let x be the number of new men joined the garrison,
The total quantity of food is = 3600(20) (1.5) kg ----------1
Now the available food will be consumed by (3600+x) men
(3600+x) (12) (2) kg --------------2
1 = 2
Solving both the equations
3600(20) (1.5) = (3600+x) (12) (2)
108000 = 86400 + 24x
21600 = 24x
X = 900
900 more men joined the garrison.
The total quantity of food is = 3600(20) (1.5) kg ----------1
Now the available food will be consumed by (3600+x) men
(3600+x) (12) (2) kg --------------2
1 = 2
Solving both the equations
3600(20) (1.5) = (3600+x) (12) (2)
108000 = 86400 + 24x
21600 = 24x
X = 900
900 more men joined the garrison.
Read the passage below and solve the questions based on it.
A book having pages between 4,000 and 5,000 is divided into four parts, each part being divided into chapters. The total number of pages in each of the four parts is the same. The ratio of the chapters across all the parts is 6:5:10:14. The number of chapters in the fourth part is 70
Q.What is the total number of pages in the book?
- a)4,000
- b)4,800
- c)4,200
- d)4,600
Correct answer is option 'C'. Can you explain this answer?
Read the passage below and solve the questions based on it.
A book having pages between 4,000 and 5,000 is divided into four parts, each part being divided into chapters. The total number of pages in each of the four parts is the same. The ratio of the chapters across all the parts is 6:5:10:14. The number of chapters in the fourth part is 70
A book having pages between 4,000 and 5,000 is divided into four parts, each part being divided into chapters. The total number of pages in each of the four parts is the same. The ratio of the chapters across all the parts is 6:5:10:14. The number of chapters in the fourth part is 70
Q.What is the total number of pages in the book?
a)
4,000
b)
4,800
c)
4,200
d)
4,600
|
Palak Yadav answered |
► According to question, A:B:C:D = 6:5:10:14
► Now in D there are 70 chapters
Therefore, A:B:C:D = 30:25:50:70 [ Multiplying Each by 5 ]
L.C.M of 30, 25, 50, 70 is 1050
So each part should have 1050 pages.
So total pages = 4 x 1050 = 4200 ans.
► Now in D there are 70 chapters
Therefore, A:B:C:D = 30:25:50:70 [ Multiplying Each by 5 ]
L.C.M of 30, 25, 50, 70 is 1050
So each part should have 1050 pages.
So total pages = 4 x 1050 = 4200 ans.
Can you explain the answer of this question below:Two cogged wheels of which one has 32 cogs and other 54 cogs, work into each other. If the latter turns 80 times in three quarter of a minute, how often does the other turn in 8 seconds? (Assume equal size cogs and equi-spaced).
- A:
24
- B:
16
- C:
32
- D:
8
The answer is a.
Two cogged wheels of which one has 32 cogs and other 54 cogs, work into each other. If the latter turns 80 times in three quarter of a minute, how often does the other turn in 8 seconds? (Assume equal size cogs and equi-spaced).
24
16
32
8
|
Dhruv Mehra answered |
Option(A) is correctLess Cogs ⇒ more turns and less time ⇒ less turns Cogs Time TurnsA 54 45 80B 32 8 ?Number of turns required= 80 x (54/32) x (8/45) = 24 times
A and B invested Rs 12,000 and Rs 18,000 respectively in a business for the whole year. At the year-end, there was a total profit of Rs 2,000. What is the share of A in the profit?- a)Rs 800
- b)Rs 1,200
- c)Rs 1,600
- d)None of these
Correct answer is option 'A'. Can you explain this answer?
A and B invested Rs 12,000 and Rs 18,000 respectively in a business for the whole year. At the year-end, there was a total profit of Rs 2,000. What is the share of A in the profit?
a)
Rs 800
b)
Rs 1,200
c)
Rs 1,600
d)
None of these
|
Glance Learning Institute answered |
Correct Answer- Option A
Three friends A, B and C started a venture with capitals in the ratio of 4:1:15. At the end of every quarter A halves his capital, while B doubles his capital and C leaves his capital untouched. This process is repeated till the end of the year. If at the end of the year B ’ s share of the profit is Rs 22,000, what is the total profit?
- a)Rs 88,000
- b)Rs 1,10,000
- c)Rs 2,25,000
- d)Rs 1,21,000
Correct answer is option 'D'. Can you explain this answer?
Three friends A, B and C started a venture with capitals in the ratio of 4:1:15. At the end of every quarter A halves his capital, while B doubles his capital and C leaves his capital untouched. This process is repeated till the end of the year. If at the end of the year B ’ s share of the profit is Rs 22,000, what is the total profit?
a)
Rs 88,000
b)
Rs 1,10,000
c)
Rs 2,25,000
d)
Rs 1,21,000
|
Bhavya Saha answered |
A man has 25 paise, 50 paise and 1 Rupee coins. There are 220 coins in all and the total amount is 160. If there are thrice as many 1 Rupee coins as there are 25 paise coins, then what is the number of 50 paise coins?- a)60
- b)80
- c)100
- d)120
Correct answer is option 'A'. Can you explain this answer?
A man has 25 paise, 50 paise and 1 Rupee coins. There are 220 coins in all and the total amount is 160. If there are thrice as many 1 Rupee coins as there are 25 paise coins, then what is the number of 50 paise coins?
a)
60
b)
80
c)
100
d)
120
|
|
Rajeev Kumar answered |
Given:
Total coin = 220
Total money = Rs. 160
There are thrice as many 1 Rupee coins as there are 25 paise coins.
Concept used:
Ratio method is used.
Calculation:
Let the 25 paise coins be 'x'
So, one rupees coins = 3x
50 paise coins = 220 – x – (3x) = 220 – (4x)
According to the questions,
3x + [(220 – 4x)/2] + x/4 =160
⇒ (12x + 440 – 8x + x)/4 = 160
⇒ 5x + 440 = 640
⇒ 5x = 200
⇒ x = 40
So, 50 paise coins = 220 – (4x) = 220 – (4 × 40) = 60
∴ The number of 50 paise coin is 60.
The first, second and third class fares between two railway stations, Patna and Lucknow were 10:8:3 and the number of first, second and third class passengers between the two stations was is 3:4:10. If total sales of the ticket is Rs 16,100, find the money obtained by the sales of second class tickets.- a)Rs 5,250
- b)Rs 5,600
- c)Rs 6,400
- d)Rs 6,650
Correct answer is option 'B'. Can you explain this answer?
The first, second and third class fares between two railway stations, Patna and Lucknow were 10:8:3 and the number of first, second and third class passengers between the two stations was is 3:4:10. If total sales of the ticket is Rs 16,100, find the money obtained by the sales of second class tickets.
a)
Rs 5,250
b)
Rs 5,600
c)
Rs 6,400
d)
Rs 6,650
|
|
Saumya Sengupta answered |
Let the fare of 1st, 2nd and 3rd class be lOx, 8x, and 3x respectively and let the no. of passengers of 1st, 2nd and 3rd class be 3y, 4y and lOy respectively, then 30xy + 32xy + 30xy = 16100 ⇒ 92xy = 16100 Hence xy = 175
Required amount = 32xy = 32 x 175 = 5600
Read the passage below and solve the questions based on it.
There are certain number of apples, guavas and oranges in a basket. The number of each variety is more than one. The ratio of the number of apples to the number of guavas is equal to the ratio of the number of guavas lo the number of oranges.Q.If the total number of fruits is 61, then find the number of guavas.- a)16
- b)20
- c)25
- d)Cannot be determined
Correct answer is option 'B'. Can you explain this answer?
Read the passage below and solve the questions based on it.
There are certain number of apples, guavas and oranges in a basket. The number of each variety is more than one. The ratio of the number of apples to the number of guavas is equal to the ratio of the number of guavas lo the number of oranges.
There are certain number of apples, guavas and oranges in a basket. The number of each variety is more than one. The ratio of the number of apples to the number of guavas is equal to the ratio of the number of guavas lo the number of oranges.
Q.
If the total number of fruits is 61, then find the number of guavas.
a)
16
b)
20
c)
25
d)
Cannot be determined
|
|
Akanksha Datta answered |
Number of apples/Number of guavas = Number of guavas/Number of oranges (Number of guavas)2 = Number of apples x Number of oranges This gives us a hint that Number of apples x Number of oranges should be a prefect square.
Now start using the options.
Option (b) satisfies the relationship (16/20 = 20/25)
Now start using the options.
Option (b) satisfies the relationship (16/20 = 20/25)
Four numbers in the ratio of 1:3:4:7 add up to give a sum of 75. Find the value of the biggest number.- a)42
- b)35
- c)49
- d)63
Correct answer is option 'B'. Can you explain this answer?
Four numbers in the ratio of 1:3:4:7 add up to give a sum of 75. Find the value of the biggest number.
a)
42
b)
35
c)
49
d)
63
|
|
Kavya Saxena answered |
Method to Solve :
Let 1:3:4:7 be 1x, 3x, 4x, 7x respectively.
1x + 3x + 4x + 7x =7515x = 75
x = 75/15
x = 5
So, 1x = 1*5 = 5
3x = 3*5 = 15
4x = 4*5 = 20
7x = 7*5 = 35
P works twice as fast as Q, whereas P and Q together can work three times as fast as R. If P, Q and R together work on a job, in what ratio should they share the earnings?- a)2:1:1
- b)4:2:1
- c)4:3:2
- d)4:2:3
Correct answer is option 'A'. Can you explain this answer?
P works twice as fast as Q, whereas P and Q together can work three times as fast as R. If P, Q and R together work on a job, in what ratio should they share the earnings?
a)
2:1:1
b)
4:2:1
c)
4:3:2
d)
4:2:3
|
|
Akanksha Datta answered |
If P is taking 3 days to do some work, then Q takes 6 days to do the same work. Now, both of them will take 2 days to complete the work. So, R takes 6 days to complete the same work.
Hence, earning should be distributed in the ratio of their efficiency, i.e., 2 : 1 : 1.
Hence, earning should be distributed in the ratio of their efficiency, i.e., 2 : 1 : 1.
Chapter doubts & questions for Ratio and Proportion - Mathematics for RRB NTPC / ASM 2025 is part of RRB NTPC/ASM/CA/TA exam preparation. The chapters have been prepared according to the RRB NTPC/ASM/CA/TA exam syllabus. The Chapter doubts & questions, notes, tests & MCQs are made for RRB NTPC/ASM/CA/TA 2025 Exam. Find important definitions, questions, notes, meanings, examples, exercises, MCQs and online tests here.
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