Question 513440
p = number of pennies
1p = value of the pennies in cents
n = number of nickels
5n = value of nickels in cents
d = number of dimes
10d = value of dimes in cents.
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d = n+5
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p = 3n
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1p + 5n + 10d = 878 cents
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3n + 5n + 10(n+5) = 878
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8n + 10n +50 = 878
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18n = 828
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n = 46
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p = 3n
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p = 3*46 = 138
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d = n+5 = 46 +5 = 51
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Always check your solution.
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1(138) = $1.38
5(46) = $2.30
10(51) = $5.10
$1.38 + $2.30 + $5.10 = $8.78
Correct.
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Always re-read the question to make sure you answer it.
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Answer:  There are 46 nickels in the bag.
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Done.