Question 1020844
So Ken paid his friend the rental cost of $6.15 (including taxes) but he paid him using only nickels ($0.05) and dimes ($0.10). If there were 3 more dimes than nickels, how many of each coin did Ken give his friend? 
Equations:
Quantity:: d = n + 3
Value::: 10n + 5d = 615 cents
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Modify::
d - n = 3
d + 2n = 123
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Subtract and solve for "n"::
3n = 120
n = 40 (# of nickels)
d = n+3 = 43 (# of dimes)
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Cheers,
Stan H.
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