Question 1117430: amanda has a total of 80 nickels and quarters. The total value of the change is $7.60. How many nickels does she have? Answer by ikleyn(52847) (Show Source):
Assume for a minute that all quarters are of the same charge as nickels, i.e. 5 cents (instead of 25 cents).
Then the full charge of 80 coins would be 5*80 = 400 cents = $4.00.
It is $3.60 less than $7.60, and the difference is due to the difference 25c-5c = 20c in charge between quarters and nickels.
So, we need to add/(to compensate) 20c for each quarter. How many times ? = 18 times.
It gives you the
Answer. 18 quarters and 80 - 18 = 62 nickels are there in the collection.
Check. 18*25 + 62*5 = 760 cents. ! Correct !
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