Question 296003
Sami has a collection of nickels and dimes that is worth $5.65. If the number of dimes were doubled and the number of nickels were increased by 8, the value of the coins would be $10.45. how many dimes does she have?
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Equations:
5n + 10d = 565 cents
5(n-8)+10(2d) = 1045 cents
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Rearrange:
n + 2d = 113
(n-8) + 4d = 209
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n + 2d = 113
n + 4d = 217
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2d = 104 
d = 52 (# of dimes)
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Substitute into n + 2d = 113 and solve for "n":
n + 2(52) = 113
n = 9 (# of nickels)
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Cheers,
Stan H.
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