Help with box on sled slope problem

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The problem involves a 20kg sled and a 10kg box on a 20-degree slope, with specific coefficients of friction provided. The user initially calculated the tension required for the box to slip as 188 N but later realized the correct answer is 155 N. The confusion stemmed from resolving forces in the context of static and kinetic friction. The user successfully solved the problem shortly after posting for help. This highlights the importance of careful force resolution in physics problems involving friction on slopes.
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Help with box on sled slope problem!

I've attempted this question and have re done the question about 3 times, getting the same answer.

A rope attached to a 20kg wood sled pulls the sled up a 20 degree snow covered hill. A 10kg wood box rides on top of the sled. If the tension in the rope steadily increases, at what value of the tension does the box slip?
coefficient of static friction between 2 wooden boxes=0.5
coefficient of kinetic friction between sled and snow=0.06

Resolving forces, I seem to keep on ending up with 188 N, but the answer is 155 N.
 
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It's ok, I figured it out, always happens, 2 minutes after I post, the answer comes to me lol.
 
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