SOLUTION: My daughter is in doing solving problems with two variables; the addition or subtraction method. We are having a lot of trouble with these. Please help...one of the questions are a

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Question 399548: My daughter is in doing solving problems with two variables; the addition or subtraction method. We are having a lot of trouble with these. Please help...one of the questions are as follows...

Gary has $4.40 in nickles and dimes. He has 10 more nickles than dimes. How many of each coin does he have?
Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website!

Let n = no. of nickeks
let d = no. of dimes
:
Write an equation for each statement:
:
"Gary has $4.40 in nickles and dimes.
.05n + .10d = 4.40
:
He has 10 more nickles than dimes.
n = d+10
:
In the 1st equation substitute (d+10) for n, solve for d
.05(d+10) + .10d = 4.40
.05d + .5 + .10d = 4.40
.05d + .10d = 4.40 - .50
.15d = 3.90
d =
d = 26 dimes, then, obviously, we have 36 nickels
:
:
Check and see if that is true, find the value using these solutions
.05(36) + .10(26) =
1.80 + 2.60 = 4.40