Sundown Rent-a-Car, a large automobile rental agency operating in the Midwest, is

preparing a leasing strategy for the next six months. Sundown leases cars from an

automobile manufacturer and then rents them to the public on a daily basis. A forecast of the

demand for Sundown's cars in the next six months follows:

Month March April May June July August

Demand 420 400 430 460 470 440

Cars may be leased from the manufacturer for either three, four, or five months. These are

leased on the first day of the month and are returned on the last day of the month. Every six

months the automobile manufacturer is notified by Sundown about the number of cars

needed during the next six months. The automobile manufacturer has stipulated that at least

50% of the cars leased during a six-month period must be on the five-month lease. The cost

per month on each of the three type of leases are $420 for the three-month lease, $400 for

the four-month lease, and $370 for the five-month lease.

Currently, Sundown has 390 cars. The lease on 120 cars expires at the end of March. The

lease on another 140 cars expires at the end of April, and the lease on the rest of these expires

at the end of May.

Use LP to determine how many cars should be leased in each month on each type of lease to

minimize the cost of leasing over the six-month period by using excel solver. How many cars

are left at the end of August?

Question