Question 647186: You invested $18,000 in two accounts paying 5% and 7% annual interest, respectively. If the total interest earned for the year was $1020, how much was invested at each rate? Whats the amount invested at 5%?
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! You invested $18,000 in two accounts paying 5% and 7% annual interest, respectively. If the total interest earned for the year was $1020, how much was invested at each rate? Whats the amount invested at 5%?
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Equation:
Quantity Eq: f + s = 18000
Interest Eq:5f +7s = 102000
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Modify the 1st equation:
5f + 5s = 5*18000
5f + 7s = 102000
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Subtract and solve for "s":
2s = 12000
s = $6000 (amt. invested at 7%)
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Solve for "f":
f + s = 18000
f + 6000 = 18000
f = $12000 (amt. invested at 5%)
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Cheers,
Stan H.
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