SOLUTION: Coco has a jar containing pennies and nickels. There is $9.20 worth of coins in the jar. If she could switch the number of pennies with the number of nickels, there would be $26.80

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Question 1060399: Coco has a jar containing pennies and nickels. There is $9.20 worth of coins in the jar. If she could switch the number of pennies with the number of nickels, there would be $26.80 worth of coins in the jar. How many pennies and nickels are in the jar?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +p+ = the number of pennies in the 1st jar
Let +n+ = the number of nickels in the 1st jar
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(1) +1%2Ap+%2B+5%2An+=+920+ ( in cents )
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And, if the numbers of pennies and nickels are switched,
(2) +1%2An+%2B+5%2Ap+=+2680+
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(1) +1%2Ap+%2B+5%2An+=+920+
(2) +5%2Ap+%2B+1%2An+-+2680+
Multiply both sides of (1) by +5+
and subtract (2) from (1)
(1) +5p+%2B+25n+=+4600+
(2) +-5p+-+n+=+-2680+
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+24n+=+1920+
+n+=+80+
and
(1) +p+%2B+5n+=+920+
(1) +p+%2B+5%2A80+=+920+
(1) +p+=+920+-+400+
(1) +p+=+520+
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There are 520 pennies and 80 nickels in the jar
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check:
(2) +n+%2B+5p+=+2680+
(2) +80+%2B+5%2A520+=+2680+
(2) +80+%2B+2600+=+2680+
(2) +2680+=+2680+
OK