Answer: x = 65
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Work Shown:
x = cost of labor per hour
3x = cost of the 3 hours of labor
3x+141 = cost of labor plus parts = total cost
3x+141 = 336
3x = 336-141
3x = 195
x = 195/3
x = 65
The hourly wage is $65 per hour for labor.
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Check:
1 hour = 65 dollars in labor costs
3 hours = 3*65 = 195 dollars in labor costs
195+141 = 336 dollars total
The answer is confirmed.