Question

Suppose a population of rhinos is shrinking by 4% each year. Ifthere are 600 rhinos this year, how many rhinos are predicted tobe in the population in 22 years?

Answer 1

Exponential growth:

$P(t)=A*(1+r)^t$

A is the initial population

r is the rate of growth in decimal form

t is the time (in years)

For the given situation:

$\begin{gathered} P(t)=600*(1+0.04)^t \\ P(t)=600*1.04^t \end{gathered}$

To find the population in 22 years evaluate the equation above for x=22

$\begin{gathered} P(22)=600*1.04^{22} \\ P(22)\approx1422 \end{gathered}$Then, the predicted population in 22 years is approximately 1422