6.4 Solve Simple Interest Applications

Before you get started, take this readiness quiz.

Solve $0.6 y = 45 .$
If you missed this problem, review the reference.

Solve $\frac{n}{1.45} = 4.6 .$
If you missed this problem, review the reference.

Find the simple interest earned after $3$ years on $\$\text{500}$ at an interest rate of $\text{6}\%.$

Find the simple interest earned after $4$ years on $\$\text{800}$ at an interest rate of $\text{5}\%.$

Find the simple interest earned after $2$ years on $\$\text{700}$ at an interest rate of $\text{4}\%.$

Find the principal invested if $\$\text{178}$ interest was earned in $2$ years at an interest rate of $\text{4}\%.$

Find the principal invested if $\$\text{495}$ interest was earned in $3$ years at an interest rate of $\text{6}\%.$

Find the principal invested if $\$\text{1},\text{246}$ interest was earned in $5$ years at an interest rate of $\text{7}\% .$

Find the rate if a principal of $\$\text{8},\text{200}$ earned $\$\text{3},\text{772}$ interest in $4$ years.

Find the rate if a principal of $\$\text{5},\text{000}$ earned $\$\text{1},\text{350}$ interest in $6$ years.

Find the rate if a principal of $\$\text{9},\text{000}$ earned $\$\text{1},\text{755}$ interest in $3$ years.

Nathaly deposited $\$\text{12},\text{500}$ in her bank account where it will earn $\text{4}\%$ interest. How much interest will Nathaly earn in $5$ years?

Areli invested a principal of $\$\text{950}$ in her bank account with interest rate $\text{3}\%.$ How much interest did she earn in $5$ years?

Susana invested a principal of $\$\text{36},\text{000}$ in her bank account with interest rate $\text{6}.\text{5}\% .$ How much interest did she earn in $3$ years?

Loren lent his brother $\$\text{3},\text{000}$ to help him buy a car. In $\text{4 years}$ his brother paid him back the $\$\text{3},\text{000}$ plus $\$\text{660}$ in interest. What was the rate of interest?

Jim lent his sister $\$\text{5},\text{000}$ to help her buy a house. In $3$ years, she paid him the $\$\text{5},\text{000} ,$ plus $\$\text{900}$ interest. What was the rate of interest?

Hang borrowed $\$\text{7},\text{500}$ from her parents to pay her tuition. In $5$ years, she paid them $\$\text{1},\text{500}$ interest in addition to the $\$\text{7},\text{500}$ she borrowed. What was the rate of interest?

Eduardo noticed that his new car loan papers stated that with an interest rate of $\text{7}.\text{5}\% ,$ he would pay $\$\text{6},\text{596}.\text{25}$ in interest over $5$ years. How much did he borrow to pay for his car?

Sean's new car loan statement said he would pay $\$\text{4},\text{866}.\text{25}$ in interest from an interest rate of $\text{8}.\text{5}\%$ over $5$ years. How much did he borrow to buy his new car?

In $5$ years, Gloria's bank account earned $\$\text{2},\text{400}$ interest at $\text{5}\%.$ How much had she deposited in the account?

Caroline got $\$\text{900}$ as graduation gifts and invested it in a $\text{10}-\text{month}$ certificate of deposit that earned $\text{2}.\text{1}\%$ interest. How much interest did this investment earn?

Adriana invested $\$\text{4},\text{500}$ for $8$ months in an account that paid $\text{1}.\text{9}\%$ interest. How much interest did she earn?

Milton invested $\$\text{2},\text{460}$ for $20$ months in an account that paid $\text{3}.\text{5}\%$ interest How much interest did he earn?

Use the simple interest formula to fill in the missing information.

Use the simple interest formula to fill in the missing information.

Use the simple interest formula to fill in the missing information.

Solve the problem using the simple interest formula.

Find the simple interest earned after $5$ years on $\$\text{600}$ at an interest rate of $\text{3}\%.$

Solve the problem using the simple interest formula.

Find the simple interest earned after $2$ years on $\$\text{8},\text{950}$ at an interest rate of $\text{3}.\text{24}\% .$

Solve the problem using the simple interest formula.

Find the simple interest earned after $8$ years on $\$\text{15},\text{500}$ at an interest rate of $\text{11}.\text{425}\% .$

Solve the problem using the simple interest formula.

Find the principal invested if $\$\text{656}$ interest was earned in $5$ years at an interest rate of $\text{4}\% .$

Solve the problem using the simple interest formula.

Find the principal invested if $\$\text{70}.\text{95}$ interest was earned in $3$ years at an interest rate of $\text{2}.\text{75}\%.$

Solve the problem using the simple interest formula.

Find the principal invested if $\$\text{15},\text{222}.\text{57}$ interest was earned in $6$ years at an interest rate of $\text{10}.\text{28}\% .$

Solve the problem using the simple interest formula.

Find the rate if a principal of $\$\text{5},\text{400}$ earned $\$\text{432}$ interest in $2$ years.

Solve the problem using the simple interest formula.

Find the rate if a principal of $\$\text{11},\text{000}$ earned $\$\text{1},\text{815}$ interest in $3$ years.

Solve the problem using the simple interest formula.

Casey deposited $\$\text{1},\text{450}$ in a bank account with interest rate $\text{4}\%.$ How much interest was earned in $2$ years?

Solve the problem using the simple interest formula.

Robin deposited $\$\text{31},\text{000}$ in a bank account with interest rate $\text{5}.\text{2}\% .$ How much interest was earned in $3$ years?

Solve the problem using the simple interest formula.

Hilaria borrowed $\$\text{8},\text{000}$ from her grandfather to pay for college. Five years later, she paid him back the $\$\text{8},\text{000} ,$ plus $\$\text{1},\text{200}$ interest. What was the rate of interest?

Solve the problem using the simple interest formula.

Lebron lent his daughter $\$\text{20},\text{000}$ to help her buy a condominium. When she sold the condominium four years later, she paid him the $\$\text{20},\text{000} ,$ plus $\$\text{3},\text{000}$ interest. What was the rate of interest?

Solve the problem using the simple interest formula.

In $10$ years, a bank account that paid $\text{5}.\text{25}\%$ earned $\$\text{18},\text{375}$ interest. What was the principal of the account?

Solve the problem using the simple interest formula.

Joshua's computer loan statement said he would pay $\$\text{1},\text{244}.\text{34}$ in interest for a $3$ year loan at $\text{12}.\text{4}\% .$ How much did Joshua borrow to buy the computer?

Solve the problem using the simple interest formula.

Caitlin invested $\$\text{8},\text{200}$ in an $\text{18}-\text{month}$ certificate of deposit paying $\text{2}.\text{7}\%$ interest. How much interest did she earn form this investment?

Solve the problem using the simple interest formula.

Airin borrowed $\$\text{3},\text{900}$ from her parents for the down payment on a car and promised to pay them back in $15$ months at a $\text{4}\%$ rate of interest. How much interest did she owe her parents?

Interest on savings Find the interest rate your local bank pays on savings accounts.

1. ⓐ What is the interest rate?
2. ⓑ Calculate the amount of interest you would earn on a principal of $\$\text{8},\text{000}$ for $5$ years.

Why do banks pay interest on money deposited in savings accounts?