Full Question Below

Question

Jolene invests her savings in two bank accounts, one paying 6 percent and the other paying 11 percent simple interest per year. She puts twice as much in the lower-yielding account because it is less risky. Her annual interest is 8579 dollars. How much did she invest at each rate?

Answer 1

I = prt

Interest = principal(rate)(time)

Total interest earned will be the sum of the amounts earned at each rate

 

If she invests $x at 11%, she invests $2x at 6%

 

8579 = x(.11) + 2x(.06)

We can multiply through by 100 if you don't like the decimals

857900 = 11x + 12x

857900 = 23x

 

x = 857900/23 = $37,300 invested at 11%

2x = $74,600 invested at 6%