Question 1096549: If there are 35 coins worth $2.20,how many nickels and dimes are in the bank? Found 2 solutions by josgarithmetic, greenestamps:Answer by josgarithmetic(39618) (Show Source):
For an informal solution, first imagine that all 35 coins are dimes; the amount would then be $3.50. But the actual amount is $2.20, which is $1.30 less than $3.50.
Next imagine replacing 1 dime with 1 nickel repeatedly. Each time you do that, the total value goes down by $0.05 (5 cents). How many times do you need to do that to get the total down to the actual amount of $2.20?
The value goes down by $0.05 each time; you need to reduce the value by $1.30. $1.30 divided by $0.05 is 26; you need to replace 26 of the dimes with nickels.
So there are 26 nickels, which means the number of dimes is 35-26 = 9.
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