Question 266704
Rosa has $3.10 in nickles and dimes. She has 10 fewer nickels than she has dimes. How many dimes and nickels does she have?
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Quantity Equation: n = d-10
Value Equation: 10d + 5n = 310 cents
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Rearrange and modify the equations:
10d - 10n = 100
10d + 5n = 310
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Subtract 1st from 2nd and solve for "n":
15n = 210
n = 14 (# of nickels)
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Since n = d-10, d = 24 (# of dimes)
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Cheers,
Stan H.
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