4 years ago

I have 30 coins consisting of nickels, and quarters. The total value of the coins is $4.10. How many of each kind do I have?

1 answer:

5 0

A=#nickels, b=#quarters

5a + 25b = 410 total value

5(a + 5b) = 410

a + 5b = 82

a + b = 30 total no. of coins

subtracting . . . 4b = 52

thus b = 13 and a = 17

13 quarters and 17 nickels = 13*25 + 17*5 = 410 = $4.10

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