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Question 163171This question is from textbook
: Melanie Morgan invested $5000 for one year, part at 9% annual interest and the rest at 12% annual interest. The interest from the investment at 9% was $198 more than the interest from the investment at 12%. How much money did she invest at 9%?This question is from textbook
: Melanie Morgan invested $5000 for one year, part at 9% annual interest and the rest at 12% annual interest. The interest from the investment at 9% was $198 more than the interest from the investment at 12%. How much money did she invest at 9%?
Answer by orca(336) About Me  (Show Source):
You can put this solution on YOUR website!
Let x represent the amount invested at 9%.
Then the amount invested at 12% is 5000 - x.
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The interest from the 9% investment is x*9%
The interest from the 12% investment is (5000 - x)*12%
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Now use the following relationship to set up an equation:
"The interest from the investment at 9% was $198 more than the interest from the investment at 12%."
x*9% - (5000 - x)*12% = 198
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Solve the equation for x.
9x - 12(5000 - x) = 19800 (after multiply both sides by 100)
9x - 60000 + 12x = 19800
21x = 79800
x = 3800
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So she invested $3800 at 9%.