Question 702394
how many nickels and dimes make up $2.30 if there are 7 less dimes than nickels?
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Quantity Equation: d = n-7
Value Equation: 5n + 10d = 230 cents
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Substitute for "d" and solve for "n":
5n + 10(n-7) = 230
5n + 10n - 70 = 230
15n = 300
n = 20 (# of nickels)
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# of dimes = n-7 = 13 
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Cheers,
Stan H.
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