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

The annual birth and death rates in a country per 1000 are 39.4 and 19.4, respectively. What will be the population of the country after 4 years, if initially the number of its residents was 10,00,000? Assume that the number of immigrants is equal to the number of emigrants every year.

  1. 12,24,888

  2. 11,80,486

  3. 10,82,432

  4. 10,20,734
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The net growth rate per 1000 is 39.4 - 19.4 = 20. This is a 2% annual growth rate. Using the compound interest formula P(1 + r/100)^n, the population after 4 years is 1,000,000 * (1.02)^4. Calculating 1.02^4 gives approximately 1.08243216, and multiplying by 1,000,000 yields 1,082,432.

Multiple choice

The population of an island is 27,000 and its national income is Rs. 52,65,000. It is forecasted that the population will increase at a compounded annual growth rate of 10% and the national income at 7%. Considering that this will go on for a period of five years, what will be the percentage of change in the per capita income of the island?

  1. Decrease by 12.913%

  2. Increase by 12.913%

  3. Increase of 13.913%

  4. Decrease of 14.913%

  5. Increase of 15.913%
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Initial per capita = 5265000 / 27000 = 195. After 5 years: Income = 5265000 * (1.07)^5 = 7382226. Population = 27000 * (1.1)^5 = 43516. New per capita = 7382226 / 43516 = 169.64. Change = (169.64 - 195) / 195 = -12.913%.

Multiple choice

It has been observed that the population of a city has been increasing exponentially at the rate of 5% per year for past 5 decades and the same trend is expected to continue. If the population was 10 million in the year 2000, by when can it be expected to touch the 15 million mark? (The exponential model is y = y0eat, take loge1.5 = 0.4054)

  1. After 8.11 years

  2. After 12.12 years

  3. After 20 years

  4. After 23.15 years
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

y = y0 * e^(at). 15 = 10 * e^(0.05 * t). 1.5 = e^(0.05 * t). ln(1.5) = 0.05 * t. 0.4054 = 0.05 * t. t = 0.4054 / 0.05 = 8.108 years.

Multiple choice

Directions: The following table shows the production of rice (in million tonnes) of three states over six years. | States | Years | | --- | --- | | 2011 | 2012 | 2013 | 2014 | 2015 | 2016 | | A | 5.2 | 5.4 | 5.8 | 6.2 | 6.5 | 6.9 | | B | 3.8 | 4.1 | 4.4 | 4.8 | 5.2 | 5.7 | | C | 4.5 | 5.2 | 5.8 | 6.4 | 6.7 | 7.4 | What is the percentage increase in the production of rice in state B from 2014 to 2016?

  1. 17.25

  2. 18.25

  3. 18.75

  4. 17.75
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Production of B in 2014 = 4.8. Production of B in 2016 = 5.7. Increase = 5.7 - 4.8 = 0.9. Percentage increase = (0.9 / 4.8) * 100 = 18.75%.

Multiple choice

The price of a certain product increased by the same percent from 1960 to 1970 as from 1970 to 1980. If its price of $1.20 in 1970 was 150 percent of its price in 1960, what was its 1980 price?
  1. $1.80
  2. $2.00
  3. $2.40
  4. $2.70
  5. $3.00
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Price in 1970 = 1.20. 1970 price is 150% of 1960 price, so 1.20 = 1.5 * P1960, P1960 = 0.80. The growth rate from 1960 to 1970 is (1.20 - 0.80)/0.80 = 0.40/0.80 = 50%. Applying the same 50% increase to 1970 price: 1.20 * 1.5 = 1.80.