Question 994601
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N=number of nickels; D=number of dimes; Q=number of quarters
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D=N
N+D+Q=10
N+N+Q=10
2N+Q=10
Q=10-2N

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$0.05N+$0.10D+$0.25Q=$1.10
$0.05N+$0.10N+$0.25Q=$1.10
$0.15N+$0.25Q=$1.10
$0.15N+$0.25(10-2N)=$1.10
$0.15N+$2.50-$0.50N=$1.10
-$0.35N=-$1.40
N=4
ANSWER 1: There are 4 nickels.
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D=N+4
ANSWER 2: There are 4 dimes.
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Q=10-2N=10-2(4)=10-8=2
ANSWER 3: There are 2 quarters. 
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CHECK:
$0.05N+$0.10D+$0.25Q=$1.10
$0.05(4)+$0.10(4)+$0.25(2)=$1.10
$0.20+$0.40+$0.50=$1.10
$1.10=$1.10