SOLUTION: My brain does not mix numbers and letters, but I'm trying to help my grandson with his summer homework. Here's one of two that he couldn't figure out. Altogether you have $3.30. If

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Question 208666: My brain does not mix numbers and letters, but I'm trying to help my grandson with his summer homework. Here's one of two that he couldn't figure out. Altogether you have $3.30. If you have 9 more nickels than dimes and 12 fewer quarters than nickels, how many of each do you have?
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
. Altogether you have $3.30. If you have 9 more nickels than dimes and 12 fewer quarters than nickels, how many of each do you have?
.
Let x = number of dimes
then
x+9 = number of nickels
x+9 -12 = x-3 = number of quarters
.
.05(x+9) + .10x + .25(x-3) = 3.30
.05x+.45 + .10x + .25x-.75 = 3.30
.40x-.30 = 3.30
.40x = 3.60
x = 3.60/.40
x = 9 (number of dimes)
.
number of nickels:
x+9 = 9+9 = 18
.
number of quarters:
x-3 = 9-3 = 6