Answer:
By producing the starters the company will save $20,000 per year.
Explanation:
production costs
direct materials $3.10 per unit
direct labor $2.70 per unit
supervision $60,000
depreciation $40,000
variable manufacturing overhead $0.60 per unit
rent $12,000
total production cost $9.20 per unit
The engineer is wrong because he is considering fixed costs like depreciation and rent that should not be included because they are independent on whether this project is approved or not. Once you take away depreciation and rent, the cost per unit will fall by $1.30 [= ($40,000 + $12,000) / 40,000 units].
Since the production cost = $9.20 - $1.30 = $7.90, which is lower than $8.40 which is the purchase cost, the company should start producing the starters at least until its sales bonce back.
By producing the starters the company will save ($8.40 - $7.90) x 40,000 units = $20,000 per year