Question 1083287
q = number of quarters
d = number of dimes

q + d  = 600
25q + 10d = 12375   (units are cents)

10x top eqn:
10q + 10d = 6000

subtract bottom eqn:
10q + 10d = 6000
-25q - 10d = -12375
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-15q = -6375
     q = -6375/-15 = 425 —>  d = 600-425 = 175
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Ans:  425 quarters, 175 dimes
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Check:  425(25) + 175(10) = 10625 + 1750 = 12375 = $123.75  (ok)