<PRE><B>Question 115769</B>
In a box, there are 25 coins consisting of quarters, dimes and nickels with a total amount of $2.75.
If the nickels were dimes, the dimes were quarters and the quarters were nickels, the total amount would be $3.75.  
How many quarters are there?
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Let # be : q=quarter, d=dimes, n=nickels
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n + d + q = 25
5n+10d+25q=275
10n+25d+5q=375
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Using a TI-83 Matrix function I get:
n=10
d=10
q=5
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Cheers,
Stan H.
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