Exercise 12–3 (30 minutes)
Per Unit
Differential
Costs
Cost of purchasing …………………..
Direct materials ………………………
Direct labor …………………………...
Variable manufacturing overhead .
Fixed manufacturing overhead,
traceable1 …………………………...
Fixed manufacturing overhead,
common ……………………………..
Difference in favor of continuing to
make the carburetors …………….
Only the supervisory salaries can be avoided if the carburetors are
purchased. The remaining book value of the special equipment is a
sunk cost; hence, the $4 per unit depreciation expense is not
relevant to this decision.
Based on these data, the company should reject the offer and should
continue to produce the carburetors internally.
Cost of purchasing (part 1) ……………………….
Cost of making (part 1) …………………………...
Opportunity cost—segment margin foregone
on a potential new product line ……………….
Total cost ………………………………………………
Difference in favor of purchasing from the
outside supplier ……………………………………
Thus, the company should accept the offer and purchase the
carburetors from the outside supplier.