A total of $80,000 is invested in two funds paying 2.3% and 3.1% simple interest . The total annual interest is $2000. How much is invested in each fund?

Answer 1

If $x is invested at 2.3%, the rest (80000-x) is at 3.1%

So, adding up the interest, we get

.023x + .031(80000-x) = 2000