A 27.76 N crate is being lowered down at a constant rate along an inclined ramp by a massless rope. Find the magnitude of force F in N if the angle between the ramp and the horizontal is 30 degrees and coefficient of kinetic friction is 0.2. See the figure attached. My attempt at solution:

Sum F y = 0
F y = F n - F g y
F n = m g cos(30)

Sum F x = F g x - F - f k = 0
F = F g x - f k
F = m g sin(30) - mu k Fn
F = m g sin(30) - 0.2(m g cos(30))

F = 27.76sin(30) - 0.2(27.76cos(30))
F = 9 N

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