Interpreting and Solving Exponential Growth and Decay Word Problems

In 1985, there were 285 cell phone subscribers in the small town of Centerville. The number of subscribers increased by 75% per year after 1985. How many cell phone subscribers were in Centerville in 1994?

• 305

• 1994

• 1000

• 43872

If you have $10, and your money doubles every year, how much money will you have in 10 years?

• $50

• $100

• $5120

• $10240

Classify the model as Exponential GROWTH or DECAY.
A=1200(.85)⁶

• Growth

• Decay

Which of the following functions shows an initial amount of $15 and an increase of 35% each year?

• y = 15(35)^x

• y = 15(1.35)^x

• y = 15(0.35)^x

• y = 35(1.15)^x

The value of a car is $15,000 and depreciates at a rate of 8% per year. What is the decay factor? Hint: decay factor is (1-r) where r is the rate as a decimal

• ^.08

• ^1.08

• .92

• 8

If the decay rate is 20%, which of the following represent the decay factor?

• 0.2

• 0.8

• 1.2

• 1.8

A flea medicine breaks down at a rate of 20% per hour. This is the rate of decay of the medicine. The initial dose is 60 milligrams. Which of the following represent the equation the models the amount of flea medicine left in an animal?

This is an example of:

• Linear Growth

• Linear Decay

• Exponential Growth

• Exponential Decay

The value of a car depreciates exponentially. Identify the decay factor is the car was worth $20,000 initially and worth $15,000 after 1 year.

• 1.33

• 0.75

• 0.66

• 0.25