SOLUTION: Could you help me find out how much John has invested? John invests twice as much money at 6% as he does at 5%. If his investments earn a total of $680 in one year. How much does h

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: Could you help me find out how much John has invested? John invests twice as much money at 6% as he does at 5%. If his investments earn a total of $680 in one year. How much does h      Log On


   

Question 300188: Could you help me find out how much John has invested? John invests twice as much money at 6% as he does at 5%. If his investments earn a total of $680 in one year. How much does he have invested at each rate?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Could you help me find out how much John has invested?
John invests twice as much money at 6% as he does at 5%.
If his investments earn a total of $680 in one year.
How much does he have invested at each rate?
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Let amt invested at 5% be "x".
Amt invested at 6% is "2x".
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Equation:
interest + interest = interest
0.05x + 0.06(2x) = 680
Multiply thru by 100 to get:
5x + 12x = 68000
17x = 68000
x = $4000 (amt. invested at 5%)
2x = 8000 (amt. invested at 6%)
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Cheers,
Stan H.
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