Question 1012772
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N=nickels; D=dimes; Q=quarters
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N=3D+15
Q=N+D=4D+15
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N+D+Q=78
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(3D+15)+D+(4D+15)=78
8D+30=78
8D=48
D=6
ANSWER 1: There are 6 dimes.
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N=3D+15=3(6)+15=18+15=33
ANSWER 2: There are 33 nickels.
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Q=4D+15=4(6)+15=24+15=39
ANSWER 3: There are 39 dimes.
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CHECK:
N+D+Q=78
33+6+39=78
78=78
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