Question 970231
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N=Number of nickels; D=number of dimes
N+D=50
D=50-N Use this to substitute for D below.
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$0.05N+$0.10D=$4.30 (This converts number of coins to value) Substitute for D.
$0.05N+$0.10(50-N)=$4.30
$0.05N+$5.00-$0.10N=$4.30 Subtract $5.00 from each side.
-$0.05N=-$0.70 Divide each side by -$0.05.
N=14 ANSWER 1: There are 14 nickels in the jar.
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D=50-N=50-14=36 ANSWER 2: There are 36 dimes in the jar.
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CHECK:
$0.05N+$0.10D=$4.30
$0.05(14)+$0.10(36)=$4.30
$0.70+$3.60=$4.30
$4.30=$4.30