Devin has a cup of quarters and dimes with a total value of $17.75. The number of quarters is 1 less than twice the number of dimes. How many quarters and dimes does Devin have?

Answer 1

q = number of quarters at 0.25 each

d = number of dimes at 0.10 each

0.25q + 0.10d = 17.75

q = 2d - 1

0.25(2d - 1) + 0.10d = 17.75

d = 30

q = 2d - 1 = 2(30) - 1 = 59

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