What are the order winners and Qualifiers for Kristen’s Cookies?
Kristen’s Cookies is conveniently located on campus and will cater to hungry students late at night. The company will not only let the students customize their cookies, but also bake them fresh. Students will have a wide variety of ingredients to choose from and this bake to order concept will ensure that cookies are to consumer’s liking. Based on this model, order qualifiers are the physical location of the company and the order winners are the unique and freshly baked cookies.
Assuming all orders are for one dozen cookies, how long will it take you to fill the first order of the night?
For one dozen cookies, ignoring the requirement of preheating the oven, it will take twenty-six minutes to fill the first order of the night. Reference Exhibit A.
If you make a mistake on a batch of cookies, how long will it take to make a new order?
The amount of time to make a new order will depend on where in the process a mistake is made. For instance, if a batch is dropped before the baking process, the batch will take an additional 8 minutes to be mixed and spooned again. If the cookies are burnt or dropped coming out of the oven, then the additional time will be 18 minutes. However, if a mistake is made during the cooling steps, the entire process has to be started again and will take the entire 26 minutes.
How many orders can you fill in a night assuming you are open four hours each night? What is the bottleneck? Should you use a capacity cushion?
Kristen’s Cookies can fill 22 orders when running at full capacity during a 4-hour night.
We can see that the upfront setup time to prepare the first order is 8 minutes before baking, while the first order is baking, subsequent orders can be processed. For the first batch, the initial step of mixing and spooning takes 8 minutes. While this first order is baking, subsequent orders may begin to be processed. Once the first order is done baking, we are immediately ready to put the next order in the oven. This follows for all subsequent orders. Essentially, this means that after the initial 8 minutes a new order comes out of the oven every 10 minutes. While an order is baking (1+9= 10min), the previous order can be cooled, packed and paid for (5+2+1= 8mins). This continues until the last order comes out of the oven. At this time, we need an additional 8 minutes (5+2+1=8mins) to complete the last order. So, this gives us a general formula of 6+2+(1+9)*n+5+2+1, this simplifies to 16+10n. This formula gives us the time it takes to process n orders. If we know we are open for 4 hours or 240 minutes, then we can solve for 16+10n=240mins, or n=22 orders (rounding down since fractional orders do not count as processed).
Washing and Mixing| 6 minutes|
Spooning| 2 minutes|
Setting thermostat and Baking| 10 minutes|
Cool off| 5 minutes|
Pack| 2 minutes|
Accept Payment| 1 minute|
Total Time| 26 minutes|
So, total time per order is 26 minutes for 1 dozen cookies, however, subsequent orders can be started in parallel to the first order. This is shown in exhibit A, which shows orders x,y, and z and the stages of the cookie baking process at any given time. Reference Exhibit A
The bottleneck is the oven, which can only bake one dozen cookies at a time.While maximum capacity is 22 orders for every 4 hour shift, given this is a start-up business and one driven by students where demand on some evenings of the week may be predictably higher or lower than other evenings, a capacity cushion should be used. Average utilization for any given resource is never 100% and although it may happen from time to time, it probably would not be true for this cookie venture -- orders just won’t come in every 10 minutes on a routine or timely basis per the production schedule nor would you always receive 22 orders for every shift. Also,...