Answer:
Materials used in production 113,120
Explanation:
The credited overehad will be 60% of direct labor
thus: 90,720/0.6 = 151,200 direct labor
Then debit for finished good is the WIP completed during the period so we can use it to solbe for material now:
Beginning WIP 100,800
Materials X
Labor 151,200
Overhead 90,720
Transferred-out (324,800)
Ending WIP 131,040
Materials = Ending WIP + transferred-out - DL - MO
Materials = 113,120