Question

This expression 12(1.0515)t models the population of elephants in a wildlife refuge after years since 1975 is the population of elephants increasing or decreasing?

Answer 1

The function for an exponential growth/decay is given as follows;

`f(x)=a(1+r)^x`

Where,

`\begin{gathered} x=\text{Number of years} \\ a=\text{initial value} \\ r=\text{rate of growth} \end{gathered}`

Observe that from the equation provided, the rate is 1.015. This means there is a growth. If there was a decay(decrease), the rate would be less than 1 because, the formula then would be;

`f(x)=a(1-r)^x`

ANSWER:

Therefore, the population of elephants is INCREASING.