Question in description.

Question

Jennifer deposited $10,000 into two bank accounts that earn simple interest. One account earns a 5% simple interest and the other account earns a 7% simple interest. At the end of the year Jennifer earned $670 in interest. How much money did she invest in the 7% simple interest account?

Answer 1

Let x = the amount of money invested at 7% interest

Let 10,000 - x = the amount of money invested at 5% interest

.07x + .05(10,000-x) = 670    Multiply both sides of the equation by 100

7x + 5(10,000-x) = 67,000

7x + 50,000 - 5x = 67,000

                       2x = 17,000

                          x = $8500 invested at 7%

10,000 - 8500 = $1500 invested at 5%