1. Exponential

2. What do you remember?
Exponential

3. Percent increase/decrease
The Equation
𝐴= 𝐴 0 1± 𝑟 𝑡
Time
Initial amount
Growth/Decay Rate

4. The Population problem
The population of Baconburg starts off at 20,000 and grows 13% each year. Write an exponential model and find the population after 10 years.
𝐴 0 = 20, 000
r = 13
t = t but substitute in 10
𝐴= 𝑡
67,891

5. The House Problem $139,500 𝐴 0 = 150000 r = 7
A house purchased for $150,000 in The value of the house depreciates at a rate of 7%. How much is the house worth in 2013
𝐴 0 =
r = 7
t = t but substitute in 11
𝐴= − 𝑡
$139,500

6. The Frog Problem 300 Frogs 𝐴 0 = 100 r = 22 t = t but substitute in 6
A population of 100 frogs increase at an annual rate of 22%. How many frogs will there be in 6 years?
𝐴 0 = 100
r = 22
t = t but substitute in 6
𝐴= 𝑡
300 Frogs

7. The Bird Problem 7046 birds 𝐴 0 = 5400 r = 3 t = t but substitute in 9
A number of birds in a forest decrease by 3% per year. Originally there were 5,400 birds. How many birds will there be in 9 years? Round to the nearest whole number.
𝐴 0 = 5400
r = 3
t = t but substitute in 9
𝐴= 𝑡
7046 birds