SOLUTION: Due to the abuse the pay phones in the school lobby are exposed to, some of them have a mind of their own and will only accept dimes and nickels. At the end of the day when they we

Algebra ->  Customizable Word Problem Solvers  -> Finance -> SOLUTION: Due to the abuse the pay phones in the school lobby are exposed to, some of them have a mind of their own and will only accept dimes and nickels. At the end of the day when they we      Log On

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Question 122512: Due to the abuse the pay phones in the school lobby are exposed to, some of them have a mind of their own and will only accept dimes and nickels. At the end of the day when they were emptied, one phone had 80 coins totaling $6.65. How many dimes had been deposited into that phone that day?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Put the amount in the phone in terms of pennies
d = number of dimes
n = number of nickels
n+%2B+d+=+80
5n+%2B+10d+=+665
d+=+80+-+n
5n+%2B+10%2880+-+n%29+=+665
5n+%2B+800+-+10n+=+665
-5n+=+-135
n+=+27
n+%2B+d+=+80
d+=+80+-+27
d+=+53
There are 53 dimes and 27 nickels in the phone
check
5n+%2B+10d+=+665
5%2A27+%2B+10%2A53+=+665
135+%2B+530+=+665
665+=+665
OK