# QUESTIONS

Chapter 7

1. Bill Vincent works for a producer of hammers that come in packages of 8 each. His job is to fill the packages with hammers, and he is expected to process 44 packages an hour. The facility where Bill works uses a kanban production system in which each container holds 11 packages of hammers. It takes 30 minutes to receive the packages he needs from the previous workstation. How many kanbans are needed for the filling process?

2. A production cell at TickTock Watch factory operates 10 hours per day and uses a pull method to supply bands to the assembly line. The bands are used at a rate of 600 per day. Each container holds 40 bands and usually waits 40 minutes in the production cell. Management wants a safety stock of 15 percent. How many containers should be used at the TickTock Watch factory for purposes of pull production?

3. Jory produces 600 units of a tires per hour and 75 units are needed to fill a container. It takes 30 minutes to receive the materials needed from the previous workstation. The company currently uses a safety stock of 20 percent. Determine the number of kanbans needed between Jory’s station and the previous process.

4. Consider the information from the above Problem. Determine how the number of kanbans and the inventory level will be affected if the time required for Jory to receive the material decreases to 10 minutes

CHAPTER 8

1. Sales for a product for the past three months have been 221, 376, and 244. Use a three-month moving average to calculate a forecast for the fourth month. If the actual demand for month 4 turns out to be 421, calculate the forecast for month 5.

2. Shady Oaks Retirement home forecasts monthly labor needs

 Month Actual Values May 37 June 46 July 43 August 44 September 48

A. Given the following monthly labor figures, make a forecast for October using a two-period moving average and a four-period moving average.

B. What would be the forecast for October using the naïve method?

C. If the actual labor figure for October turns out to be 49, what would be the forecast for November using each of these models?

D. Compare the accuracy of these models using the mean absolute deviation (MAD).

E. Compare the accuracy of these models using the mean squared error (MSE).

3. Two different forecasting models were used to forecast sales of a popular drink on a college campus. Actual demand and the two sets of forecasts are shown. Use MAD to explain which method provided a better forecast.

 Period Actual Demand Forecast 1 Forecast 2 1 85 73 82 2 82 80 83 3 87 79 85 4 90 87 92 5 93 95 97 6 93 97 96