Simple Interest: Charles deposited $12,000 in the bank. He withdrew $5000 after one year....

[sburke78]

Hello, By chance does anyone know how to solve the problem below. This question was provided in the pre-algebra online extra test question practice but it does not explain how to find the solution. It just says the solution is 9% and I have not been able to figure out how they arrived at this solution.

Thank you.

Charles deposited $12,000 in the bank. He withdrew $5000 from his account after one year. If he receives a total amount of $9340 after 3 years, find the rate of simple interest.

 

[Dr.Peterson]

A good place to start might be to check their answer. At 9%, how much would he get at the end? If your answer is $9340, you can write out the work you did, and then replace the 9% with x to find an equation you could have solved to get the answer.

Please show your work (on this check, or on an attempted solution), so we can guide you through whatever part is giving you trouble.

I have to add, though, that this doesn't sound like a prealgebra problem, even if "prealgebra" includes the beginnings of algebra.

 

[Steven G]

Hello, By chance does anyone know how to solve the problem below. This question was provided in the pre-algebra online extra test question practice but it does not explain how to find the solution. It just says the solution is 9% and I have not been able to figure out how they arrived at this solution.

Thank you.

Charles deposited $12,000 in the bank. He withdrew $5000 from his account after one year. If he receives a total amount of $9340 after 3 years, find the rate of simple interest.

The first year Charles had $12,000 in his account.
The 2nd year he had $7,000 in his account
The 3rd year he had $7,000 in his account

Ignoring interest for a moment he should have $7,000 after 3 years (do you see why?). So how much interest was earned?

Here is a big hint. Since this is simple interest, if Charles put in ($12,000 + $7,000 +$7,000) =$26,000 all at once for ONE year he would earn the same amount of interest compared to the three year scenario you have above.

See what you can do with this information!