Answer: 25 nickels
Explanation:
EQUATIONS:
quantity: n + d = 63
value: 5n + 10d = 505
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Divide thru the 2nd equation by 5 to get:
n + 2d = 101
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Subtract that from the 1st equation:
-d = -38
d = 38 (# of dimes)
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Substitute that into n+d=63 to solve for "n":
n + 38 = 63
n = 25 (# of nickels)