A population of 1,750 cheetahs decreases by 11% per year. How many cheetahs will there be in the population after 10 years? Round your answer to the nearest whole number.

A. 4969

B. 486

C. 546

D. 1640

The answer is C. 546.

If a population decreases by 11%, that means that 89% (100% - 11% = 89%) of cheetahs remains each number. 89% can be expressed as 0.89, so to calculate the change of the population, we must each year multiply the number of cheetahs by 0.89.

After 1 year: 1750 * 0.89 ≈ 1558

After 2 years: 1558 * 0.89 ≈ 1387

After 3 years: 1387 * 0.89 ≈ 1234

After 4 years: 1234 * 0.89 ≈ 1098

After 5 years: 1098 * 0.89 ≈ 977

After 6 years: 977 * 0.89 ≈ 870

After 7 years: 870 * 0.89 ≈ 774

After 8 years: 774 * 0.89 ≈ 689

After 9 years: 689 * 0.89 ≈ 613

After 10 years: 613 * 0.89 ≈ 546