Answer:
Particulars Make Buy Incremental cost
Manufacturing cost $474,000 $474,000
Purchase $393,420 ($393,420)
(474,000*$0.83)
Fixed Cost $94,800 ($94,800)
(474,000*$0.20)
Total relevant cost $474,000 $488,220 ($14,220)
Conclusion: The company should make the fitting and the incremental savings will be $14,220