Question 707182
Taylor has a box of coins that she uses when she plays poker with her friends. The box currently contains 44 coins, consisting of pennies, dimes, and quarters. The number of pennies is equal to the number of dimes, and the total value is $4.37. How many quarters does she have in the box? 
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Quantity Eq::: p + d + q = 44 coins
Quantity Eq::: p = d
Value Eq::::::1*p + 10d + 25q = 437 cents
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Substitute d for "p":
2d + q = 44
11d+ 25q=437
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Modify for elimination  of the "d" terms
22d + 11q = 11*44
22d + 50q = 874
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Solve for "q":
39q = 390
q = 10 (# of quarters)
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Cheers,
Stan H.
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