Question 999030
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Q=number of quarters 
N=number of nickels=3Q
D=number of dimes=Q-2
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$0.25Q+$0.05N+$0.10D=$4.80
$0.25Q+$0.05(3Q)+$0.10(Q-2)=$4.80
$0.25+$0.15Q+$0.10Q-$0.20=$4.80
$0.50Q=$5.00
Q=10
ANSWER 1: She has 10 quarters.
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N=3Q=3(10)=30
ANSWER 2: She has 30 nickels.
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D=Q-2=10-2=8
ANSWER 3: She has 8 dimes.
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CHECK:
$0.25Q+$0.05N+$0.10D=$4.80
$0.25(10)+$0.05(30)+$0.10(8)=$4.80
$2.50+$1.50+$0.80=$4.80
$4.80=$4.80