Shamrock Inc. has been manufacturing its own shades for its table lamps. The company is currently operating at 100% of capacity, and variable manufacturing overhead is charged to production at the rate of 50% of direct labour costs. The direct materials and direct labour costs per unit to make the lampshades are $4.60 and $5.90, respectively. Normal production is 48,500 table lamps per year. A supplier offers to make the lampshades at a price of $13.70 per unit. If Shamrock Inc. accepts the supplier's offer, all variable manufacturing costs will be eliminated, but the $46,400 of fixed manufacturing overhead currently being charged to the lampshades will have to be absorbed by other products.

a) Prepare the incremental analysis for the decision to make or buy the lampshades.

b) Should Shamrock buy the lampshades or not?