Force projection onto body's axis

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Bismuth
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Hey PhysicsForums. Long time reader looking for some assistance

Homework Statement



[PLAIN]http://img205.imageshack.us/img205/3923/physicsg.jpg

2. The attempt at a solution

I'm pretty sure the idea is to find the unit position vector to point A, and the force vector F.

I found the unit position vector to be u = (-4/6)i +(4/6)j + (2/6)k, and the force to be F = (560cos60sin30)i + (560cos60cos30)j + (560sin60)k

Dotting them together gives me 230 lb, but Mastering Engineering doesn't agree with me. Can anyone point out where I went awry?

Thanks for reading!
 
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