1. Exponential Growth
Relationship where the initial (starting) amount increases by the same percent over a given period of time

2. y = C(1+r)t
C is the initial amount
r is the rate of change
t is the time
y is the final amount

3. The rate of change is always expressed as a decimal in the equation…not a percent
To change from a % to a decimal, divide by 100 or move the decimal point two places to the left

5. Compound Interest The equation is: A = P(1+r)nt n
Compound interest is a special application of exponential growth
The equation is:
A = P(1+r)nt n
P is the principal (initial amount)
r is the rate of interest
n is the number of times the interest is compounded each year
Annually = once per year
Biannually = twice per year
Quarterly = four times per year
Monthly = twelve times per year
t is the number of years the money is invested
A is the current amount of the investment

7. Exponential Decay
Relationship where the initial (starting) amount decreases by the same percent over a given period of time

8. y = C(1 - r)t
All variables have the same meaning as they do in the equation for exponential growth.