problem solving

Question

A man has invested $ 10, 000 in two funds that pay interest rates of 7% and

8 %, respectively. If he receives yearly interest $ 772, how much is invested in each fund?

Answer 1

.08x + .07(10-x) = .772

.01x = .772 -.7 = .072

x = .072/.01= 7.2 = $7,200 invested in 8%

$2,800 invested in 7%

.08(7200) + .07(2800)

= 576 + 196

= $772 interest one year