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Santa Claus helps solving coin problem
Problem 1
In a collection of nickels, dimes and quarters, there are twice as many dimes as nickels and 3 fewer quarters than dimes.
If the total value of the coins is $4.50, how many of each type of coin are there
Solution
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* Santa Claus came to us to help solving this problem *
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He took 3 quarters from his pocket and added it to the collection.
The "value" of the collection became $4.50 + 3*$0.25 = $5.25 = 525 cents.
Now we can combine all the coins in groups in a way that each group contains 2 dimes, 1 nickel and 2 quarters.
Each group worth is 2*10 + 5 + 2*25 = 75 cents.
How much groups do we have now?
= 7.
OK. Then 7 groups contain 2*7 = 14 dimes, 7 nickels and 2*7 = 14 quarters.
Now we need to return 3 quarters to Santa.
Thank you, Santa !!
Answer. The collection has 14 dimes, 7 nickels and 14-3 = 11 quarters.
In this calculation we can not make a mistake.
Therefore, please check it on your own if the solution is correct.
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Thank you Santa again !!
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