Answer:
Reduction in work in progress = $7500
Explanation:
given data
time = 10 hours
time = 15 hours
worth  = $1,500
to find out
reduction in work in process value
solution
we find work in progress  by this formula
work in progress  = Flow rate  × Cycle Time   .......................1
so Initial work in progress is
Initial work in progress  = (1 per hour)  × 10 hours = 10
and Final work in progress is here
Final work in progress  = (1 per hour) × 15 hours = 15
so
Initial work in progress  value = 10  × 1500
Initial work in progress  value= $15000
and
Final work in progress   value =15  × 1500
Final work in progress   value = $22500
so
Reduction in work in progress = $22500 - $15000
Reduction in work in progress = $7500