Answer:
x = 150
Explanation:
360 = 1/3x + (x-20) + (x-10) + 40
360 = 1/3x + x - 20 + x - 10 + 40
360 + 20 + 10 - 40 = 1/3x + 2x
350 = 1/3x + 2x
350 = 7/3x
x =

x =

x = 150
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360 = 1/3 Ă— 150 + 150 - 20 + 150 - 10 + 40
360 = 50 + 150 - 20 + 140 + 40
360 = 200 - 20 + 180
360 = 180 + 180
360 = 360
same value the answer is good