SOLUTION: John has a total of 13 coins in his pocket. Of the 13 coins, they are all either quarters or dimes. The total value of the coins is $2.50. How many quarters does John have in his p
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Question 248649: John has a total of 13 coins in his pocket. Of the 13 coins, they are all either quarters or dimes. The total value of the coins is $2.50. How many quarters does John have in his pocket? Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! John has a total of 13 coins in his pocket. Of the 13 coins, they are all either quarters or dimes. The total value of the coins is $2.50. How many quarters does John have in his pocket?
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Equations:
Quantity Equation: q + d = 13
Value Equation::::25q+10d = 250
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Multiply thru the 1st equation by 10.
10q + 10d = 130
25q + 10d = 250
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Subtract the 1st equation from the 2nd and solve for "q":
15q = 120
q = 8 (# of quarters)
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Cheers,
Stan H.
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