In investing &5500 of a couples money, a financial planner put some of it into savings paying 6% annual simple interest. The rest was invested in a riskier minimall development plan paying 12% annual simple interest. The combined interest earned the first year was $522. How much money was invested at each rate
Let amount invested at 6% be S
Then amount invested at 12% is: 5,500 - S
We then get: .06S + .12(5,500 - S) = 522
.06S + 660 - .12S = 522
.06S - .12S = 522 - 660
- .06S = - 138
S, or
You should be able to find the amount invested at 12%