This problem, is seriously bugging me:

A collection of nickels, dimes, and quarters consists of 12 coins with a total value of $1.45. If the number of nickels is 2 less than the number of dimes, how many of each coin are contained in the collection?

I thought, I had it right the first time, but my totals didn't add up to 1.45. I don't understand what I am doing wrong.

The three equations I came up with are:

x + y + z = 12

x = y - 2 or x - y = -2

5x + 10y + 25z = 145

Are my equations wrong?