Random
Growth or Decay
Growth or Decay
Percent Rate
Word Problems
100
What is the initial amount and growth factor for the function f(x)=2(3)x
initial amount=2
growth factor= 3
100
How do I know if the exponential relationship below is growth or decay?
y = 3(0.56)x
Decay has a b value or decay factor less than 1.
100
For the exponential function y=15(3)x, what is the factor, and does the function represent growth or decay?
Exponential Growth
Factor: 3
100
Is this exponential growth or decay?
What is the percent growth/decay rate?
y=5(0.5)^x
Exponential Decay
50%
100
2243
200
Erin invested $19,800 in a bank account that pays an annual interest rate of 5.3%. How much is in Erin’s account after 9 years?
$31,515.23
200
Do the following equations represent exponential growth, decay, or neither?
a) y=3.5(0.3)x
b) y=2(3)x
c) y=5x+6
a) Decay
b) Growth
c) Neither (It's linear! y=mx+b)
200
Larry invested $27,000 in a savings account that pays an annual interest rate of 1.8%, compounded yearly. How much is in Larry’s account after 5 years?
$29,519.07
200
Is this exponential growth or decay?
What is the percent growth/decay rate?
y=5(1.3)^x
Exponential Growth
30%
200
What will be the cost in 17 years?
$32,313.27
300
A student puts $100 in a savings account when they enter Kindergarten. If they don't make any more deposits how much will the account be worth when they graduate in 12 years? The interest rate is 3.09%.
$144.08
300
y=2(1.13)x
Does this function represent exponential growth or decay? What is the growth/decay RATE?
Exponential Growth
Rate: 0.13 or 13%
300
f(x)=7(1.07)x
Does this function represent exponential growth or decay? What's the percent growth/decay RATE?
Exponential Growth.
Rate: 0.07 or 7%.
300
Is this exponential growth or decay?
What is the percent growth/decay rate?
y=1(0.01)^x
Exponential Decay
99%
300
16,941 people
400
a) What is the y-intercept?
b) Is it Growth or Decay?
a) (0,1)
b) growth
400
y=5(0.97)x
Does this function represent exponential growth or decay? What is the growth/decay RATE?
Exponential Decay
Rate: 0.03 or 3%
400
Does the graph represent exponential growth or decay?
Exponential Growth
400
Is this exponential growth or decay?
What is the percent growth/decay rate?
y=1/2(0.7)^x
Exponential Decay
30%
400
Is the function exponential growth or decay?
Write the equation to represent the graph. 
Decay
y = 2400 (0.5x)
500
Write the equation in the following table:
(hint, simply plug in the initial value and growth factor)
y= 5(2)x
500
Ms. Parker purchased a car for 26,400 and every year it decays by 12%. What can she expect the value of her car to be after 3.5 years?
y=26400(.88)3.5=$16,876.92
500
Annual sales of a fast food restaurant are $530,000 and increasing at a rate of 5% per year. What will the annual sales be in 6 years? (show the equation and answer)
530,000(1.05)6 =$710,250.69
500
Is this exponential growth or decay?
What is the percent growth/decay rate?
y=1/2(1.07)^x
Exponential GROWTH
7%
500
If you put $500.00 into an account and the account earns a 3% yearly interest rate. How much will be in the account after 5 years?
Round the nearest cent!
$579.64