Multiple choice

According to a survey, the population of a city increased by 10% per year for two years and then decreased by 10% per year for the next two years. If the population 4 years ago was 1,00,000, then what would be the current population of the city?

  1. 1,08,900

  2. 98,010

  3. 96,100

  4. 92,400

  5. 99,000
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Population = 100000 * 1.1 * 1.1 * 0.9 * 0.9 = 100000 * 1.21 * 0.81 = 100000 * 0.9801 = 98010.

AI explanation

Using the successive percentage change formula, we multiply the initial population by the growth factors for each year. The calculation is 1,00,000 multiplied by 1.10 multiplied by 1.10 multiplied by 0.90 multiplied by 0.90. This simplifies to 1,00,000 multiplied by 1.21 multiplied by 0.81. The current population of the city is 98,010.

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