Quantitative Aptitude

Percentage

482 Questions
All Successive Percentage Changes 177 Population Growth and Depreciation 103 Fractional Base Multiplication 58 Reverse More-Than and Less-Than Comparisons 38 Income, Expenditure, and Savings 33 Price and Consumption 30 Election Votes and Margins 10 Fake Weight and Faulty Measures 10 Venn Diagram Percentages 9 Passing Marks Shifts 5 Fresh vs. Dry Mixture 2

Percentage Questions

Multiple choice

Two newpapers $A$ and $B$ are published in a city. It is known that $25$% of the city population reads $A$ and $20$% reads $B$ while $8$% reads both $A$ and $B$. Further, $30$% of those who read $A$ but not $B$ look into advertisements and $40$% of those who read $B$ but not $A$ also look into advertisements while $50$% of those who read $A$ and $B$ look into advertisements. Then the percentage of the population who look into advertisement is:
  1. $12.8$
  2. $13.5$
  3. $13.9$
  4. $13$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

P(A only) = 25 - 8 = 17%. P(B only) = 20 - 8 = 12%. P(Both) = 8%. Ads = (0.3 * 17) + (0.4 * 12) + (0.5 * 8) = 5.1 + 4.8 + 4.0 = 13.9%.

Multiple choice

In a cinema hall, the charge per person is Rs. $200$. On the first day, only $60\%$ of the seats were filled. The owner decided to reduce the price by $20\%$ and there was in increase of $50\%$ in the number of spectators on the next day. The percentage increase in the revenue on the second day was.
  1. $50$
  2. $40$
  3. $30$
  4. $20$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Day 1: Revenue = 200 * 0.6 * N = 120N. Day 2: Price = 200 * 0.8 = 160. Spectators = 0.6N * 1.5 = 0.9N. Revenue = 160 * 0.9N = 144N. Increase = (144 - 120) / 120 = 24 / 120 = 20%.

Multiple choice

In a survey of brand preference for toothpastes, $82$ of the population (number of people covered for the survey is $100$) liked at least one of the brands: I, II and III. $40$ of those liked brand I, $25$ liked brand II and $35$ liked brand III. If $8$ of those asked, showed liking for all the three brands, then what percentage of those liked more than one of the three brands?
  1. $13$
  2. $10$
  3. $8$
  4. $5$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Let n(I)=40, n(II)=25, n(III)=35, and n(I intersection II intersection III)=8. Total union = 82. Using the inclusion-exclusion principle: n(I U II U III) = n(I)+n(II)+n(III) - [n(I int II) + n(II int III) + n(III int I)] + n(I int II int III). 82 = 40+25+35 - S + 8, where S is the sum of double intersections. 82 = 108 - S, so S = 26. The number of people liking exactly two brands is S - 3*n(I int II int III) = 26 - 3*8 = 2. Total liking more than one is 2 + 8 = 10.

Multiple choice

Mr. X, a business man had the income in the year $2000$, such that he earned a profit of $20$% n his investment in the business. In the year $2001$, his investment was less by Rs. $5000$ but still had the same income (Income=Investment+Profit) as that in $2000$. Thus, the percent profit earned in $2001$ increased by $6$%. What was his investment in $2000$?
  1. Rs. $1,02,000$
  2. Rs. $1,05,000$
  3. Rs. $1,50,500$

  4. Data inadequate

  5. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Let investment in 2000 be I. Profit in 2000 is 0.2I, so income is 1.2I. In 2001, investment is I - 5000 and income is 1.2I. The profit percent in 2001 is (1.2I - (I - 5000)) / (I - 5000) = 0.26. Solving 0.2I + 5000 = 0.26I - 1300 gives 0.06I = 6300, so I = 105,000.

Multiple choice

A number is increased by $20$% and then again by $20$%. By what percent should the increased number be reduced so as to get back the original number?
  1. $19\cfrac { 11 }{ 31 } $%
  2. $30\cfrac { 5 }{ 9 } $%
  3. $40$%
  4. $44$%
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Original number = 100. After 20% increase: 120. After another 20% increase: 120 * 1.2 = 144. To return to 100, reduction needed = 44. Percent reduction = (44 / 144) * 100 = 4400 / 144 = 30.555...% = 30 5/9%.

Multiple choice

The price of wheat falls by 16% By what percentage a person can increase the consumption of wheat so that his overall budget does not change?

  1. 16%

  2. 18%

  3. 18.5%

  4. 19%
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

If price falls by 16%, it becomes 84% of original. To keep budget same, consumption * price = constant. New consumption * 0.84 * Original Price = Original Consumption * Original Price. New consumption = Original / 0.84 = 1.1904 * Original. Increase is 19.04%.