Final answer:
The actual number of hours worked during the past period is 22,500 hours.
Step-by-step explanation:
To find the actual number of hours worked during the past period, we can use the labor efficiency variance formula:
Actual Hours - Standard Hours = Labor Efficiency Variance
Given that the labor efficiency variance was $8,000 favorable, we can set up the equation:
Actual Hours - (2.5 hours per unit x 9,000 units) = $8,000
Simplifying the equation, we have:
Actual Hours - 22,500 hours = $8,000
Therefore, the actual number of hours worked during the past period is:
Actual Hours = 22,500 hours + $8,000
Actual Hours = 30,500 hours = b. 22,500 hours.