1. Objective - To solve problems involving exponential growth or decay functions.
A colony of 10,000 ants can increase by 15%
in a month. How many ants will be in the colony
after 1 year?

2. A baby weighing 7 pounds at birth may increase
in weight by 11% per month for the first 12 months.
How much will the baby weigh after 1 year?

3. A deposit of $1500 in an account pays
interest compounded annually. How much
will be in the account after 8 years?

4. A population of 10 hamsters will triple every
year for 4 years. What will be the population
after 4 years?
Percent Increase
Growth Factor
Population is 200%
more than last year.
Population is 3 times
as much as last year.

5. Exponential Decay Functions
A radioactive material decays at 10% per year.
How much of the 12 pound material will be left
after 20 years?

6. A car purchased for $24,500 will depreciate at a
rate of 18% per year for the first 6 years. Write an
equation and graph over the first 6 years.
$30,000
$20,000
$10,000

7. Compare Growth and Decay Models
Exponential Growth
Exponential Decay
$100 growth at 10%
for 5 years.
$100 depreciate at 10%
for 5 years.
160
140
120
100 80 60 40 20
160
140
120
100 80 60 40 20

8. Classify each as exponential growth or
exponential decay. 1) 4)
Exponential
Growth
Exponential
Decay 2) 5)
Exponential
Growth
Exponential
Decay 3) 6)
Exponential
Growth
Exponential
Growth

9. Find the value of a downtown office building that
cost 12 million dollars to build 20 years ago and
depreciated at 9% per year.