Hi all,

I think this is a very simple problem but yet I can't seem to get the right answer for some reason. Please let me know if my logic is off.

At a certain diner, a hamburger and coleslaw cost $3.59, and a hamburger and french fries cost $4.4. If french fries cost twice as much as coleslaw, how much do french fries cost?

(A) $0.3
(B) $0.45
(C) $0.6
(D) $0.75
(E) $0.9

First I set up the three equations

H + C = $3.59
H + F = $4.40
F = 2C

So I solved for the answer and I got C = $0.81.....

I also tried backsolving using the equations above and I couldn't seem to get the right answer, which is E.

Can someone please explain why?

Thanks.