<PRE><B>Question 388122</B>
Bill has 10 coins, all of which are dimes and quarters. 
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If his dimes were quarters and his quarters were dimes, his coins would total 30 cents more. 
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How many quarters does Bill have? 
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Equations:
Quantity: d + q = 10
10q+25d -(10d+25q) = 30
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Modify:
d + q = 10 
15d -15q = 30
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Modify:
d + q = 10
d - q = 2
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Subtract:
2q = 8
q = 4 (# of quarters)
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Cheers,
Stan H.
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