Question 745011
There are 52 coins in a purse. Some of them are quarters, and some are dimes. 
The total value of all coins is $7.45. how many were quarters and how many were dimes? 
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Quantity Eq: d + q = 52 coins
Value Eq::: 10d+25q = 745 cents
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Modify for elimination:
10d + 10q = 520
10d + 25q = 745
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Subtract and solve for "q":
15q = 225
q = 15 (# of quarters)
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Solve for "d":
d + q = 52
d + 15 = 52
d = 37 (# of dimes)
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Cheers,
Stan H.
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