A customer wants delivery to be ensured between 10 am and 2 pm. Your truck leaves the factory at 4 am and the time taken to reach the customer is normally distributed with an average of 8 hrs and a standard deviation of 1 hr.
What is the process capability ratio of the process?
If you want to improve the ability of the delivery process to a 6-sigma process, what would be the new mean and standard deviation of the delivery time you should target? Can you recommend one practical action to achieve the target?
This solution shows how to calculate a process capability ratio and make improvements with the six sigma process.