Finding coefficient of kinetic friction

1. The problem statement, all variables and given/known data

A 100 N force directed 37° below the horizontal is applied to a 30 kg object on a horizontal surface. If the magnitude of the acceleration of the object is 1.3 m/s2, what is the coefficient of kinetic friction (μk) between the object and the surface?

2. Relevant equations

F = ma

3. The attempt at a solution

I drew the body diagram and tried calculating the net force in the x direction.
This is what I got:

F = Fpx (the 100 N force) – Ffr
Fpx is 100cos37 and Ffr is μmg, so
ma = 79.86 – 294μ

I plugged in 1.3 for a and got 0.24 for the answer.
The correct answer is 0.12.
Not sure where I went wrong, any help would be appreciated. Thanks!

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