Answer:
32
Step-by-step explanation:
77 quarters and dimes
q + d = 77
subtract q from both sides
d = 77 - q
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A collection of quarters and dimes is worth $12.50 (1250 cents)
25q + 10d = 1250
substitute for d
25q + 10(77 - q) = 1250
distribute
25q + 770 - 10q = 1250
Combine like terms
15q + 770 = 1250
subtract 770 from both sides
15q = 480
divide both sides by 15
q = 32
