IainRourke
New member
- Joined
- Mar 20, 2016
- Messages
- 1
Hi, first time posting.
I have a problem that's been bugging me.
A company sells hammers. From historical sales info, it is known that there is a 5% probability that a customer will be sold a faulty hammer. The manager would like to reduce this probability to 1%. He plans on random sampling to inspect hammers as they come off the production line. If a defective hammer is found it will be removed before it gets passed on to the sales distributors.
The he question is,what percentage of the hammers coming off the production line should be sampled in order to give the manager a 99% confidence that any given customer will be sold a working hammer.
Obviously if 0% of the hammers are inspected, the percentage of finding a defect will still be 5%. If 100% are inspected then there will be a 0% chance of finding a defect. What function should I use to calculate the sampling percentage for a desired confidence.
I thought of using binomial, but I guess that works for whole numbers, where the absolute numbers are known. Can this be done from the perspective of percentages.
Thanks,
Iain.
I have a problem that's been bugging me.
A company sells hammers. From historical sales info, it is known that there is a 5% probability that a customer will be sold a faulty hammer. The manager would like to reduce this probability to 1%. He plans on random sampling to inspect hammers as they come off the production line. If a defective hammer is found it will be removed before it gets passed on to the sales distributors.
The he question is,what percentage of the hammers coming off the production line should be sampled in order to give the manager a 99% confidence that any given customer will be sold a working hammer.
Obviously if 0% of the hammers are inspected, the percentage of finding a defect will still be 5%. If 100% are inspected then there will be a 0% chance of finding a defect. What function should I use to calculate the sampling percentage for a desired confidence.
I thought of using binomial, but I guess that works for whole numbers, where the absolute numbers are known. Can this be done from the perspective of percentages.
Thanks,
Iain.