Question 840425: 18 coins with a total value of 2.85.the coins are dimes and quarters. How many of each type of coin is there? Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! 18 coins with a total value of 2.85.the coins are dimes and quarters. How many of each type of coin is there?
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Quantity:: d + q = 18 coins
Value::::10d +25q = 285 cents
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Modify:
2d + 2q = 2*18
2d + 5q = 57
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Subtract and solve for "q":
3q = 21
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q = 7 (# of quarters)
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Solve for "d"
d + 7 = 18
d = 11 (# of dimes)
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Cheers,
Stan H.
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