Question

A country's population in 1991 was 15 million. In 2001 it was 16 million. Estimate the population in 2005 using exponential growth formula. Round your answer to the nearest million.

Answer 1

let N = 15 e^(kt), where N is in million, t is in years since 1991 and k is a constant

when t = 10 , N = 16
16 = 15e^(10k)
1.0666667 = e^(10k)
ln 1.0666667 = 10k
k = .006456852

then when t = 14
N = 15e^(14(.00645852)) = 16.418

So to the nearest million it would still be 16 million