Answer:
(b) 9800
Step-by-step explanation:
The balance for the month is ...
(starting WIP) + (units started) - (units shipped) = (ending WIP)
3000×0.60 + (units started) - 10,000 = 4000×0.40
(units started) = 1600 + 10,000 -1800 . . . . subtract the left-side constants
units started = 9800 . . . . . . . simplify
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If there were any changes in inventory, they would be figured in as well. In this problem, the only inventory is work in process (WIP).