Exponential Growth: Final Value
How to find the final value of exponential growth: formula, 1 example, and its solution.
Formula
Formula
If a value shows exponential change (growth or decay),
use this formula.
A = A0(1 + r)t
A: Final value
A0: Initial value
r: Rate of change (per time period)
t: Number of time period
Example
Example
Solution
The initial value of the population is 10,000.
So A0 = 10000.
The population increases at a rate of 7% per year.
So r = 0.07/year.
Write the unit [per year].
The final value is the value 12 [years] later.
And the unit of the rate is [per year].
So write 12 years in [years]:
t = 12 years.
A0 = 10000
r = 0.07
t = 12
So the expected population A is
A = 10000(1 + 0.07)12.
(1 + 0.07) = 1.07
It says
assume 1.0712 = 2.252.
So 10000⋅1.0712 = 10000⋅2.252.
10000⋅2.252 = 22520
So 22520 is the answer.