Exponential Functions Mixed Practice

Which of the following represents an exponential growth function whose y-intercept is 50?

• y = 50(.05)^x

• y = 50x - 4

• y = (2)^x + 50

• y = 50(1.4)^x

Is the following function an example of decay or growth? f(x) = 2(1.25)^x

• Exponential Growth

• Exponential Decay

What is the x-intercept of the exponential function graphed?

• (0 , 1)

• (0 , -2)

• There are no x-intercepts due to the horizontal asymptote at y = 0

• x < -2

The expression f(t) = 12(1.015)^t models the population of elephants in a wildlife refuge after t years since 1975. Is the population of elephants increasing or decreasing?

• Increasing

• Decreasing

A new savings account is opened with $400 and gains 3% every year. What is the exponential function?

• f(x)=400(1+3)^x

• f(x)=400(1-0.03)^x

• f(x)=400(1+0.03)^x

• f(x)=400(0.03)^x

What does the y-intercept of the graph represent?

• The amount of grams the material is gaining.

• The amount of grams the material is losing.

• The amount of grams remaining after so many years.

• The initial amount of grams.

The expression f(t) = 12(1.015)^t models the population of elephants in a wildlife refuge after t years since 1975. What does the value 12 represent?

• The predicted increase in number of elephants in the refuge each year.

• The predicted decrease in number of elephants in the refuge each year.

• The number of years it will take for the elephant population to stop increasing.

• The initial amount of elephants in the park.

What type of function is y = 7(5/4)^x?

• Exponential Growth

• Exponential Decay

• Linear

• None of the above

What type of function is f(x)=2(1/7)^x ?

• Exponential Growth

• Linear

• Exponential Decay

• None of the Abovee

Which of the situations below would represent an exponential function? (choose all that apply)

• A worker makes $8 an hour

• A workers pay doubles every 5 years

• A savings account earns 3% interest every month

• A savings account earns $0.50 interest every month

• 3 bacteria are added to the total population every day