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- Need help to calculate the predicted defects per million for a given mean, standard deviation and specification limits.

Hi All

Assuming normal distribution I am trying to understand how to calculate the expected number of defects I would get from given specification limits.

For example assume a process mean of 51 and a standard deviation of 0.75 with a lower specification limit of 48.5 and a higher specification limit of 51.5

How do I calculate the lower and upper defects that would fall outside of the specification limits?

Would appreciate any help. Thanks!

Assuming normal distribution I am trying to understand how to calculate the expected number of defects I would get from given specification limits.

For example assume a process mean of 51 and a standard deviation of 0.75 with a lower specification limit of 48.5 and a higher specification limit of 51.5

How do I calculate the lower and upper defects that would fall outside of the specification limits?

Would appreciate any help. Thanks!