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In a library 5 percent books are in English, 10 percent of the remaining are in hindi and 15 percent of the remaining are in Sanskrit. The remaining 11628 books are in French. Then find the total number of books in the library.
Answer – c) 16000 Explanation : Let total books are A, then (95/100)*(90/100)*(85/100)*A = 11628
A solution contains 10% of salt by weight. On evaporation 15 litre of water evaporates and now concentration of salt becomes 20 percent. Find the initial quantity of solution
Answer – b) 30ltr Explanation : Let initial quantity is x litre final, salt = (x/10)/ (x – 15) = 20/100
A student has to get 40 percent marks to pass an examination. He got 60 marks but fails by 20 marks. Find the maximum marks of the examination.
Answer –b) 200 Explanation : (40/100)*M – 20 = 60 (M is the maximum marks)
The number of seats in a cinema hall is decreased by 12 percent and the price of tickets also decreased by 4 percent. Find the change in the collection of revenue.
Answer –a) decrease 15.52% Explanation : Let initial seats = 100 and cost per seat = 100, so initial revenue = 10000 now final revenue = 88*96 = 8448 % percent change in revenue = [(10000 – 8448)/10000]*100 = 15.52%
A trader marks the price at 8 percent higher than the original price. Due to the hike in demand he again increases the price by 10 percent. How much percent profit he gets.
Answer – b) 18.8% Explanation : Suppose initial price = 100 Then final price = 100*(108/100)*(110/100) = 118.8 So percent profit = 18.8
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.
Answer – c) 17820 Explanation : 15000*(11/10)*(12/10)*(9/10) = 17820
One type of liquid contains 20 percent milk and in other liquid it contains 30 percent milk. If 4 parts of the first and 6 parts of the second are taken and formed a new liquid A. Find the percentage of milk in third liquid.
Answer – a) 26 Explanation : milk = 20 and water = 80 (in 1 liquid) milk = 30 and water = 70 (in 2 liquid) milk in final mixture = 20*4 + 30*6 = 260 so (260/1000)*100 = 26%
A man has 2000 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.
Answer – b) 2640 Explanation : 2000 + 400 + 240 = 2640 (400 in first year and 240 is added in the second year)
1000 sweets need to be distributed equally among the school students in such a way that each student gets sweet equal to 10% of total students. Then the number of sweets, each student gets.
Answer – a) 10 Explanation : No of students = T. Each student gets 10% of T. So, T students get T^2/10 sweets.
T^2/10 = 1000. We get T =10
If the price of an article is increased by 15%, then by how much the household should decrease their consumption so as to keep his expenditure same.
Answer – a) 13(1/23) % Explanation : Decrease in expenditure = (15/115)*100 = 300/23 %
If the price of an article is increased by 15%, then by how much the household should decrease their consumption so as to keep his expenditure same.
Answer – 1.13(1/23)% Explanation : Decrease in expenditure = (15/115)*100 = 300/23 %
The ratio between male and female in a city is 3: 7. The children percentage among the males and females of the city is 25 and 30 percent respectively. If the number of adult males in the city is 18000, then find the population of the town?
Answer – 2.80000 Explanation : Males and females are 3x and 7x respectively (3x)*75/100 = 18000. X = 8000 so total population = 10*8000 = 80000
Pankaj gave 50 percent of the amount to akash. Akash in turn gave twofifth of the amount to venu. After paying a bill of 500 rupees, venu now have 8000 rupees left with him. Find the amount hold by pankaj initially.
Answer – 2. 42500 Explanation : Let pankaj have P amount initially [[(50/100)*P]*2/5 – 500] = 8000
P = 42500
Rakesh spent 30 percent of his monthly income on food items. Of the remaining amount he spent 60 percent on clothes and bills. Now he save fiveseventh of the remaining amount and the he saves 120000 yearly, then find his monthly income.
Answer – 2. 50000 Explanation : Let monthly income is P (70/100)*P*(40/100)*5/7 = 10000
P = 50000
Weight of A and B are in the ratio of 3:5. If the weight of A is increased by 20 percent and then the total weight becomes 132 kg with an increase of 10 percent. B weight is increased by what percent.
Answer – 3. 4% Explanation : Weight of A and B are 3x and 5x.
Initial weight before increase = (132*100)/110 = 120 8x = 120. X = 15 Initial weight of A and B are 45 and 75 kg respectively.
New weight of A = 54 so weight of B = 132 – 54 = 78.
So % increase = [(7875)/75]*100 = 4 %
When the price of rice is increased by 25 percent, a family reduces its consumption such that the expenditure is only 10 percent more than before. If 40 kg of rice is consumed by family before, then find the new consumption of family.
Answer – 2.35.2 Explanation : Suppose initially price per kg of rice is 100 then their expenditure is 4000.
Now their expenditure is only increased by only 10% i.e – 4400.
Increased price of rice = 125.
So new consumption = 4400/125 = 35.2
The price of rice is increased by 20 percent and a person decrease his consumption by 15 percent, so his expenditure on rice is
Answer – 1.increase by 2 percent Explanation : Let initial price of rice – 100 and new price of rice – 120 suppose initial consumption is 100kg and new consumption is 85kg Initial expenditure = 10000 New expenditure = 10200 (200/10000)*100 = 2 percent increase
A salary is 40 percent more than B. B’s salary is 30 percent less than C. If the difference between the salary of C and A is 1200 rupees, then what is the monthly income of C
Answer – 2.60000 Explanation : A = (140/100)*B
B = (70/100)*C
[(100/70) – (140/100)]*B = 1200.
B = 42000.
C = (100/70)*42000 = 60000
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.)
Answer – 4.46kg 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 = 46.1
One type of liquid contains 20 percent of milk and second type of liquid contains 40 percent milk. If 4 part of the first and 6 part of the second are mix, then what is the percent of water in the mixture.
Answer – 3.68% Explanation : Do these type of question by taking 100 litre water = 80ltr and 60ltr in first and second mixture respectively now percent of water = [(80*4 + 60*6)/1000]100 = 68%
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