SuperPart, an auto parts distributor, has a large warehouse in the Chicago region and is deciding on a policy for the use of TL or LTL transportation for inbound shipping. LTL shipping costs $1 per unit. TL shipping costs $800 per truck plus $100 per pickup. Thus, a truck used to pick up from three suppliers costs 800+3*100 = $1100. A truck can carry up to 2,000 units. SuperPart incurs a fixed cost of $100 for each order placed with a supplier. Thus an order with three distinct suppliers incurs an ordering cost of $300. Each unit costs $50 and SuperPart uses a holding cost of 20%. Assume that product from each supplier has an annual demand of 3,000 units.
a) What is the optimal order size and annual cost if LTL shipping is used? What is the time between orders?
b) What is the optimal order size and annual cost if TL shipping is used with a separate truck for each supplier? What is the time between orders?