Exponential Equations and Logarithms

What values of b make an exponential growth function?

• b > 0
• b <1
• b > 1
• 0 < b < 1

What values of b make an exponential decay function?

• b > 0
• b < 1
• b > 1
• 0 < b < 1

The value of a car is $15,000 and depreciates at a rate of 8% per year. What is the decay factor (the multiplier)?

• ^.08

• ^1.08

• .92

• 8

Suppose a culture of bacteria begins with 5000 cells and dies by 30% each year. Write an equation that represents this situation.

• y=5000(0.7)^x
• y=30(5000)^x
• y=5000(1.3)^x
• y=5000x^x

What is the growth for the function: f(x) = 800(0.85)^x?

• 800

• 0.85

• 0.15

• x

You bought a Boston Whaler in 2004 for $12,500. The boat's value depreciates by 7% a year. How much is the boat worth in 2012?

• $11,625

• $6994.77

• $21,477

• $875

An adult takes 800 mg of ibuprofen. Each hour, the amount of ibuprofen in the person’s system decreases by about 29%. How much ibuprofen is left after 6 hours? 

• 101
• 102
• 103
• 104

Denise has $80 in a savings account that earns 10% annual interest.

To the nearest cent, how much will she have in 3 years?

• $106.48

• $26.48

• $8

• $104

Use the function, N = 14,000(.96)^t. Where N is the number of employees and t is the number of years.

How many employees will there be after 3 years?

• 14,000 employees

• 12,386 employees

• 40,360 employees

• 15,748 employees

Kimi invests $4,000 at 3% interest compounded continuously. How much money will she have in 4 years?