Answer:
Number of actual hours worked = Â 17,550 hours
Explanation:
Efficiency variance in labour hours = labour efficiency variance/standard labour cost/ hour
The standard labour cost per hour = $24
= 1,200/24= 50 hours
Labour variance (in hours) = Actual labour hours- Standard hours for the actual units
The standard labour hours allowed for the actual 875 cranes made:
= 20  × 875 =  17,500 hours
let the actual  hours be " y "
50 = y - 17500
y = 50 + 17500
y= 17,550 hours
Number of actual hours worked = Â 17,550 hours