SOLUTION: John invested $7000 for one year. He invested part of it at 8% and the rest at 12%. At the end of the year he earned $764 in interest. How much did he invest at each rate?
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-> SOLUTION: John invested $7000 for one year. He invested part of it at 8% and the rest at 12%. At the end of the year he earned $764 in interest. How much did he invest at each rate?
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Question 197004: John invested $7000 for one year. He invested part of it at 8% and the rest at 12%. At the end of the year he earned $764 in interest. How much did he invest at each rate? Answer by Mathtut(3670) (Show Source):
You can put this solution on YOUR website! let x and y be the amounts invested at 8% and 12% respectively
:
x+y=7000.........eq 1
.08x+.12y=764....eq 2
:
rewrite eq 1 to x=7000-y and plug this value into eq 2
:
.08(7000-y)+.12y=764
:
560-.08y+.12y=764
:
.04y=204
:
y=5100.....invested at 12%
:
x=7000-y=7000-5100=1900......invested at 8%
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