Total available time 96 hours/week

Model 3 Model X

Total processing time 1 hour/unit 2 hours/unit

Total target time 500 units/week 100 units/week

Capacity cushion 15.0%

1.) How many assembly lines are needed to meet weekly production targets? (we are ignoring setup times and batch sizing; round up to the nearest whole number)

2.) Now suppose you only have 8 assembly lines. In addition, assume that you produce Model 3 cars in lots (or batches) of 100. In addition, assume that you produce Model X cars in lots (or batches) of 20. Each change in lot (or "batch") size takes 5 hours. (Imagine having to change the configuration of the machines, the materials/colors to install, etc.)

3.) Now suppose you produce Model 3 in lot size of 10 units. You also change the lot size of Model X to 2 units.

Assuming you have 8 assembly lines, what is the maximum number of cars you can produce in a week?

4.) If there is a shortage in the available time, what is the impact of batch size on total production (scale)?

5.) What is the relationship between batch size and the total required time for production?

6.) Based on your responses in #4 and #5 is it always best to make the batch size as large as possible? Can you think of situations where the increasing batch size is not always the best approach?