Answer and Explanation:
The computation is shown below;
a) The In-house purchasing cost last year is
= Fixed costs + Variable costs
=$85,000 + Total number of purchase orders × cost per order
= $85,000 + 1400 × 15
= $106,000
b)
The outsourcing cost is
Outsourcing cost = Fixed costs +Variable costs
= $100,000 + Total number of purchase orders × cost per order
= $100,000 + 1400 × 5
= $107,000
c) Total number of purchase orders = 1600
In-house purchasing cost = 85,000 + 1600 × $15 = $109000
Outsourcing cost = $100,000 + 1600 × $5 = $108000
Yes, David should outsource as the outsourcing cost is less than the in-house purchasing cost.