The wheat harvesting season in Saskatchewan is short, and farmers deliver their truckloads of wheat to a giant central storage bin within a 2-week span. Because of this, wheat-filled trucks waiting to unload and return to the fields have been known to back up for a block at the receiving bin. The central bin is owned cooperatively, and it is to every farmers benefit to make the unloading/storage process as efficient as possible.

The cost of grain deterioration caused by unloading delays and the cost of truck rental and idle driver time are significant concerns to the cooperative members. Although farmers have difficulty quantifying crop damage, it is easy to assign a waiting and unloading cost for truck and driver of $18.5 per hour.

During the 2-week harvest season, the storage bin is open and operated 15 hours per day, 7 days per week, and can unload 35 trucks per hours according to an exponential distribution ( i.e. coefficient of variation = 1).

Full trucks arrive all day long (during the hours the bin is open) at an average interval of 2 minutes with a standard deviation of 2 minutes.

As mentioned, the cooperative uses the storage bin heavily only 2-weeks per year. Some farmers feel that adding another bin would improve the systems performance dramatically. Other farmers feel that enlarging the bin is a better option rather than adding another bin.

Analyze the two options by answering the two questions (a) and (b) on page 7 and 8.

(a) Compare the performance measures of the two options indicated in the table below and comment which option you would recommend to the manager and why.

Performance Measures	Current: 1 bin	Proposal 1 = 2 bins
Average utilization of the system
Average number of trucks waiting to be unloaded
Average number of trucks being unloaded
Average number of trucks in the system
Average time a truck must wait before being unloaded
Average time to unload a truck
Average time a truck spends in the system

(b) As mentioned, the cooperative uses the storage bin heavily only 2-weeks per year. Farmers estimate that enlarging the bin would cut unloading cost by 50% next year. It would cost $9,000 to do so during the off-season. Would it be worth the expense to enlarge the storage area? Justify.