Question 1086291: Dave has 60 coin, all dimes and nickels, worth $4.80. How many of each type of coin does he have? Found 2 solutions by ikleyn, addingup:Answer by ikleyn(52925) (Show Source):
Let N be the number of nickels.
Then the number of dimes is (60-N).
The value equation is
5N + 10*(60-N) = 480 cents.
Simplify and solve for N:
5N + 600 - 10N = 480 ====> -5N = 480 - 600 ====> -5N = - 120 ====> N = 24.
Answer. 24 Nickels and 60-24 = 36 dimes.
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You can put this solution on YOUR website! d+n = 60 subtract n from both sides:
d = 60-n I'll use this value for d next.
0.10d+0.05n = 4.80 substitute for d:
0.10(60-n)+0.05n = 4.80 distribute the 0.10 over the terms in parenthesis (Distributive Properties of Multiplication)
6-0.10n+0.05n = 4.80 subtract 6 from both sides and resolve n on left:
-0.05n = -1.2 divide both sides by 0.05, and remember -/- = + Use your calculator.
