Transcript Process Capability (Example)

Process Capability (Example)
•
Food served at a restaurant should be between 38o C and 49o C when it is
delivered to the customer. The process used to keep the food at the correct
temperature has a process standard deviation of 2 o C. What is the process
capability of the process?
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If the mean temperature of the food prior to delivery is 43.5 o C, what
proportion of all meals will be delivered at an acceptable temperature?
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If management wants to ensure that only 0.1% of meals are delivered either
too warm or too cold, what specifications should they set for delivery
temperature?
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What other course of action could management take to make sure that only
0.1% of meals are delivered either too warm or too cold?
Process Capability (Example)
Food served at a restaurant should be between 38o C and 49o C when it is delivered to the customer.
The process used to keep the food at the correct temperature has a process standard deviation of 2 o C.
What is the process capability of the process?
Process Capability (Example)
Food served at a restaurant should be between 38o C and 49o C when it is delivered to the customer.
The process used to keep the food at the correct temperature has a process standard deviation of 2 o C.
What is the process capability of the process?
utl  ltl
Cp 
6
49 - 38
 .92
6(2)
Process Capability (Example)
If the mean temperature of the food prior to delivery is 43.5 o C, what proportion
of all meals will be delivered at an acceptable temperature?
Process Capability (Example)
If the mean temperature of the food prior to delivery is 43.5 o C, what proportion
of all meals will be delivered at an acceptable temperature?
Process Std. Dev' n  2
Tolerance limit   5.5 or
49 - 38
2
5.5
 2.75 standard deviations from the mean
2
Z table tells us that 2.75 correspond s to .4970 therefor e .9940 is proportion served at an acceptable temperatu re.
Therefore, a unit falls outside limit if it is
Process Capability (Example)
If management wants to ensure that only 0.1% of meals are delivered either too warm or too cold,
what specifications should they set for delivery temperature?
Process Capability (Example)
If management wants to ensure that only 0.1% of meals are delivered either too warm or too cold,
what specifications should they set for delivery temperature?
1.00  .001  .999
Two  tail  .999/2  .4995
Z  3.29 standard deviations
x
 3.29, x  6.58
2
43.5  6.58  50.08
43.5 - 6.58  36.92
Process Capability (Example)
What else could management do?