<PRE><B>Question 1021773</B>
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D=dimes; Q=quarters
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D+Q=18
D=18-Q
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$0.10D+$0.25Q=$3.15
$0.10(18-Q)+$0.25Q=$3.15
$1.80-$0.10Q+$0.25Q=$3.15
$0.15Q=$1.35
Q=9
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D=18-Q=18-9=9
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ANSWER: There are 9 dimes and 9 quarters.
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CHECK:
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$0.10D+$0.25Q=$3.15
$0.10(9)+$0.25(9)=$3.15
$0.90+$2.25=$3.15
$3.15=$3.15
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</PRE>