Lennie is a worker for Clean&Clean Co., a car wash company….

Lennie is a worker for Clean&Clean Co., a car wash company. It seems that the company’s business is pretty good. We observed that on average 15 customers arrive every hour. The arrival is Poisson distributed.  The average car washing time is 2 minutes per car, following an exponential distribution. What percentage of the time is Lennie washing cars?

The following is a product structure tree for a toy called z…

The following is a product structure tree for a toy called zigzag robot (Z-robot). The manufacturer receives an order of 50 units of Z-robot that should be ready in week 10. The lead times for the components are Z (2 weeks), A (1 week), B (1 week), C (1 week), D (1 week), and E (3 weeks). None of these items has inventory on hand. In which week some units of item A should be received?

The UMD bookstore expects to sell about 9,000 books in manag…

The UMD bookstore expects to sell about 9,000 books in management area next year. We understand the annual carrying cost is currently $16 per title. Every time when the bookstore needs to order a book, it must spend $75 for transportation. We assume that the bookstore opens 300 days a year. What is the EOQ?

Duluth Machinery Company (DMC) is a famous producer of minin…

Duluth Machinery Company (DMC) is a famous producer of mining tools. Currently DMC supplies its customers with 10,000 mining drills each year. This demand has been consistent in recent years. The setup cost for manufacturing mining drills is $40. If stored in warehouse of DMC, every mining drill costs $.60 per year. DMC can make 500 mining drills per day. The daily sales is about 50 mining drills each business day. What is the maximum inventory level of mining drills at DMC?