SOLUTION: Walt made an extra $12,000 last year from a part-time job. He invested part of the money at 7% and the rest at 9%. He made a total of $970 in interest. How much was invested at 7%?

Algebra ->  Customizable Word Problem Solvers  -> Finance -> SOLUTION: Walt made an extra $12,000 last year from a part-time job. He invested part of the money at 7% and the rest at 9%. He made a total of $970 in interest. How much was invested at 7%?      Log On

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Question 181040: Walt made an extra $12,000 last year from a part-time job. He invested part of the money at 7% and the rest at 9%. He made a total of $970 in interest. How much was invested at 7%?

Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
.07x+.09(12,000-x)=970
.07x+1080-.09x=970
-.02x=970-1080
-.02x=110
x=-110/-.02
x=5,500 amount invested @ 7%
12,000-5,500=6,500 amount invested @ 9%
Proof:
.07*5,500+.09*6,500=970
385+586=970
970=970