Question

In 2000, the population of a county was 25,300,987. The population decreased at a rate of 2% each year. What was the population in 2008?

Answer 1

Answer: In 2008 the population was 21,525,144

Explanation:

You need to use the following formula for Exponential decay:

`P=P_0(1-r)^t`

Where
`P_0` is the initial population in the year 0,
`r` is the rate of decay and
`t` is the time.

In this case, you can identify that:

`P_0=25,300,987\\\\r=2\%\\\\t=8`

Therefore, substituting these values into the formula for Exponential decay, you get:

`P=P_0(1-r)^t\\\\P=(25,300,987)(1-(2)/(100))^8\\\\P=21,525,144`

Then, in 2008 the population was 21,525,144