Log inSign up for FREE
Library

03 - Exponential Growth & Decay Word Problems

Last updated over 4 years ago
35 questions

Exponential Growth and Decay Functions

Exponential growth occurs when a quantity increases by the same factor over equal intervals of time.


Exponential decay occurs when a quantity decreases by the same factor over equal intervals of time.

For exponential growth, the value inside the parentheses is greater than 1 because r is added to 1.

For exponential decay, the value inside the parentheses is less than 1 because r is subtracted from 1.

Let's practice finding the growth/decay factors:

1

A bank will pay you a 3% per year interest on your account.

What is the growth/decay factor?

1

A car depreciates in value 8% per year.

What is the growth/decay factor?

1

The value of the house increases by 15% per year.

What is the growth/decay factor?

1

Donovan's investment lost 4.5% interest last year.

What is the growth/decay factor?

1

Minh's saving account earned him 0.25% interest last month.

What is the growth/decay factor?

1

Emma's salary will increase by 1.75% each year.

What is the growth/decay factor?

1

Joe's charity organization has seen a loss of 12.25% over the last year.

What is the growth/decay factor?

1

Florida's alligator population has decreased by 2.5% the last 5 years.

What is the growth/decay factor?

1

The sales of laptops has increased by 37.5% this year.

What is the growth/decay factor?

1

Taxes have increased by 6.375% .

What is the growth/decay factor?

Let's complete some examples together.

1

The population of a city is 50,000 and is growing 3% each year. Determine the population of the city after 5 years. Round your answer to the nearest whole number.

1

A $6000 investment has a 7% loss each year. Determine the value of the investment after 3 years. Round your answer to the nearest cent.

1

The cells in a science experiment double every hour. How many cells would there be if the experiment began with 15 cells after 6 hours?

Now, complete the remaining problems for homework. Show your work in the space provided.

1

The starting salary for a new employee is $25,000. The salary for this employee increases 4% annually. Determine the employee’s salary after 15 years. Round your answer to the nearest cent.

1

The population of a city is 3,000,000 and is decreasing by 2% each year. Determine the population after 10 years. Round your answer to the nearest whole number.

1

You put $250 in a savings account that earns 2% annual interest compounded yearly. You do not make any deposits or withdrawals. How much will your investment be worth in 6 years? Round your answer to the nearest cent.

1

In 2017, a person purchased a car for $25,000. The value of the car decreased by 14% annually. Determine the value of car in 2021 when they traded it in. Round your answer to the nearest cent.

1

In a scientific study, the number of insects triples every 2 months. The study began with a sample of 30 insects. Determine the number of insects after 1 year.

1

An investment doubles every 8 years. What is the value of a $500 investment after 40 years?

1

During an economic recession, a charitable organization found that its donations dropped by 1.1% per year. Before the recession, its donations were $390,000. Estimate the amount of the donations 5 years after the start of the recession. Round your answer to the nearest cent.

1

Suppose the acreage of forest if decreasing by 2% per year because of development. If there are currently 4,500,000 acres of forest, determine the amount of forest land after 7 years. Round your answer to the nearest whole number.

1

Suppose one of your ancestors invested $500 in 2006 in an account paying 4% interest compounded annually. Find the account balance after 2021. Round your answer to the nearest cent.

1

Suppose you invest $1500 in an account paying 4.75% interest. Find the account balance after 25 years with the interest compounded annually. Round your answer to the nearest cent.

1

A $10,500 investment has a 15% loss each year. Find the value of the investment after 4 years. Round your answer to the nearest cent.

1

A city of 140,000 people has a 1% annual decrease in population. Determine the city's population after 10 years. Round your answer to the nearest whole number.

1

The starting salary for a new employee is $25,000. The salary for this employee increases by 8% per year. What is the salary after 3 years?Round your answer to the nearest cent.

1

An investment of $750 is placed in an account paying 5.25% interest compounded annually. Find the account balance after 7 years. Round your answer to the nearest cent.

1

Suppose a new car is worth $21,000. Its value decreases by 18% each year. Find the value of the car after 5 years. Round your answer to the nearest cent.

1

A $25,000 purchase has a 12% decrease in value per year. Determine the value of the purchase after 9 years. Round your answer to the nearest cent.

1

An investment of $400 doubles in value every 5 years. Determine the value of the investment after 20 years.

0

Please upload pictures of your work if you didn't use the space provided.

0

Please upload pictures of your work if you didn't use the space provided.

0

Please upload pictures of your work if you didn't use the space provided.

0

Please upload pictures of your work if you didn't use the space provided.

0

Please upload pictures of your work if you didn't use the space provided.