<PRE><B>Question 948395</B>
D=Dimes; N=Nickels
N=D+12
$0.05N+$0.10D=$5.10 Substitute for N
$0.05(D+12)+$0.10D=$5.10
$0.05D+$0.60+$0.10D=$5.10 Subtract $0.60 from each side.
$0.15D=$4.50 Divide each side by $0.15
D=30 ANSWER 1: There were 30 dimes.
N=D+12=30+12=42 ANSWER 2: There were 42 nickels.
CHECK:
$0.05(N)+$0.10(D)=$5.10
$0.05(42)+$0.10(30)=$5.10
$2.10+$3.00=$5.10
$5.10=$5.10

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