SOLUTION: How can $3,960 be invested, part of it at 4% and the remainder at 5%, so that the two investments will produce the same amount of interest?

Question 476289: How can $3,960 be invested, part of it at 4% and the remainder at 5%, so that the two investments will produce the same amount of interest?
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
How can $3,960 be invested, part of it at 4% and the remainder at 5%, so that the two investments will produce the same amount of interest?
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Equation:
0.04x - 0.05(3960-x) = 0
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4x - 5(3960-x)
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4x -5*3960 + 5x = 0
9x = 5*3960
x = $2200 (amt. to invest at 4%)
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3960 - x = 3960-2200 = $1760 (amt. to invest at 5%)
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Cheers,
Stan H.
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