posted by Mathew on .
I had a problem to solve, and I don't get how to make equations from this problem.
Mrs. Chans math class contributed 2 dollars and $1 coins to an earthquake relief fund. the number of $1 coins contributed was 8 less than 5 times the number of $2 coins contributed. if class raised total of 160 bucks, how many coins of each type was collected?
This also has to be solved by the elimination method, but what equations do I have to work with?
I don't know how to solve using 2 equations, but I can solve it using one equation
n = $2.00 coins
5n - 8 = $1.00 coins
2.00n = value of $2.00 coins
1.00(5n - 8) = value of $1.00 coins
2.00n + 1.00(5n - 8) = 160.00
2.00n + 5.00n - 8.00 = 160.00
7.00n = 168.00
n = 24
24 coins @ $2.00 = $48.00
5(24)- 8 = 112 coins @ 1.00 = $112.00
Thanks a lot :)