A newspaper carrier has %5.75 in change. He has ten more quarters than dimes but two times as many nickles as quarters. how many coins of each type does he have?

dimes ---- x

quarters ---- x+10
nickels ---- 2(x+10) = 2x+20

10x + 25(x+10) + 5(2x+20) = 575
10x + 25x + 250 + 10x + 100 = 575
45x = 225
x = 5

So he has 5 dimes, 15 quarters and 30 nickels

check:
5 dimes = 50 cents
15 quarters = 375 cents
30 nickels = 150 cents
total = 575 cents = $5.75

My answer is correct