Calculating Frictional Force: Solving for u in a Horizontal Curve | Physics Help

[mixedtape_15]

I really am not getting this physics stuff...again I thought I had this one figured out but it doesn't seem to be right.
So the question...
A 49.2 kg car is moving at 12.6 m/s around a horizontal curve whose radius is 31.3 m. What is the magnitude of the fictional force required to keep the car from sliding?

and this is what I did..
I found my net force for x and y
Fy = may
Fy = 0
N- W = 0
N = mg

Fx = max
fs = max
u x N = m(v^2/r)

so then I substituted in my N and got
u x mg = m(v^2/r)

and I solved for u (frictional force...I'm just using u for the term)

u x (49.2kg)(9.81m/s^2) = (49.2kg)(12.6^2/31.3m)

and it works out to be 0.517 and the computer is telling me I'm wrong once again. so I must be wrong.

 

[OlderDan]

The question does not ask you to find μ. It asks you for the frictional force.

 

[mixedtape_15]

Thank you! I have some serious problems with reading these things wrong.