Algebra need help please

Question

The population of the world in 1987 was 5 billion and the relative growth rate was estimated at 2 percent per year. Assuming that the world population follows an exponential growth model, find the projected world population in 2025. Round your answer to 2 decimal places in billions.

Answer 1

About 10.6 billion. 5(1.02)^t where t equals 38. Use the rule of 72 for a quick estimate. The population would double in 72/2 = 36 yrs.