Population growth at three percent

Statement

A small town has $40\,000$ inhabitants today and grows by $3\%$ per year. How many inhabitants will it have in $15$ years, if the growth rate stays constant?

Solution

The population follows $N(t) = N_0\,(1+i)^t$. $N(15) = 40\,000\cdot 1{.}03^{15} = 40\,000\cdot 1{.}557967 \approx \boxed{62\,319\ \text{inhabitants}}.$