Asked by Anonymous

A total of 10,000 is invested into two funds paying 7.5% and 9% simple interest. The combined annual income for the two funds is $849. Determine how much is invested at each rate
Answered by Steve
If $x is at 7.5%, then the rest (10000-x) is at 9%. So, add up the interest:

.075x + .09(10000-x) = 849
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