Phantom Company has beginning and ending Work-in-Process Inventories that are 45% and 10% complete, respectively. Materials are added at the beginning of the process. If first-in, first-out (FIFO) process costing is used, the total equivalent units for materials will equal the number of units:

Yes

Explanation:

Since the Materials are added at the beginning of the process, by the time the process ends all  units whether Completed or Work in Process will have 100% of materials added to them.Thus the Equivalent units will be 100 % completed with regards to materials for all outputs.

C) started into the process during the period.

Explanation:

Since materials are added at the beginning of the production process, all units started in the process during the period will be completed at least regarding materials, so the total equivalent units for materials = number of units started in the period.

For example, you are manufacturing doors, all the wood necessary to produce each door is added at the moment the production process starts, so it doesn't matter how advanced the conversion process is, all the materials will be included.  

c.

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