Kristen's Cookie Company

1. How long will it take you to fill a rush order?

Step Time needed to complete the step

Washing bowl and mixing the ingredients 6 minutes

Spooning the cookies onto the tray 2 minutes

Putting the cookies in the oven and setting the oven 1 minute

Cookies bake 9 minutes

Taking cookies off the oven and cooling down 5 minutes

Packing a dozen cookies 2 minutes

Accept payment 1 minute

Total time 26 minutes

The processing time to fill a rush order of one dozen cookies is 26 minutes.

2. How many orders can you fill in a night, assuming you are open four hours each night?

The oven is the bottleneck because it has the smallest capacity (it can only bake one tray at a time), thus the capacity of the whole process is equal to the capacity of the oven. The oven cycle time is 10 minutes (including 1 minute set up), which means that only 6 trays can be baked per hour.

It takes 26 minutes to bake the first tray, 10 minutes is the cycle time, and Kristen's Cookies open for 240 minutes.

26+ 10 (N-1) = 240 (N is number of orders, N-1 because the first order already counted)

N=22.4

Kristen's Cookies can fill 22 orders of one dozen cookies per night.

3. How much of your own and your roommate's valuable time will it take to fill each order?

Kristen's valuable time is 8 minutes, which includes washing the bowl and mixing the ingredients (6 minutes), and spooning the cookies onto the tray (2 minutes).

The roommate's valuable time is 4 minutes, which includes setting the oven (1 minute), remove cookies from the oven (0 minutes), pack (2 minutes), and accepts payment (1 minute).

4. For Kristen Cookies, develop a Gantt chart of the activities and the resources (Kristen, Roommate, and Oven). Determine the amount of idle time Kristen and Roommate has for each dozen cookies produced. What is the time for Kristen and roommate if the orders are for two-dozen cookies (of the same type) or three-dozen?

The following Gantt shows 6 process cycles dictated by the bottleneck. The oven's cycle time is 10 minutes, which allows an output of 6 dozen cookies per hour.

The processing time for one dozen cookies is 26 minutes, Kristen's value time in the process is 8 minutes, and

...