SOLUTION: When the charity collected all of its tin cans from convenient stores, they contained 80% more pennies than nickels. If the combined value of the pennies and nickels was $22.10, ho

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Question 1153170: When the charity collected all of its tin cans from convenient stores, they contained 80% more pennies than nickels. If the combined value of the pennies and nickels was $22.10, how many nickels did the tin cans contain?
Answer by greenestamps(13198) About Me  (Show Source):
You can put this solution on YOUR website!


Solving the problem mentally, with the "80% more pennies than nickels" I would say for every 5 nickels there are 9 pennies.

Then each group of 5 nickels and 9 pennies has a value of 34 cents.

The total $22.10, divided by 34 cents, gives 65 groups.

Finally, since each group contains 5 nickels, the number of nickels is 65*5 = 325.

Formally....

Let x = number of nickels
Then 1.8x = number of pennies

The total value of the nickels at 5 cents each and the pennies at 1 cent each is $22.10, or 2210 cents:

5%28x%29%2B1%281.8x%29+=+2210
5x%2B1.8x+=+2210
6.8x+=+2210
x+=+2210%2F6.8+=+325

ANSWER: 325 nickels