Question

Last year, Carmen had
$20,000
to invest. She invested some of it in an account that paid
9%
simple interest per year, and she invested the rest in an account that paid
5%
simple interest per year. After one year, she received a total of
$1680
in interest. How much did she invest in each account?

Answer 1

.09x + .05(20000-x) = 1680