Question

If a product is comprised of 10 independent parts with each having 3 sigma quality performance (without mean shift), the probability of the entire product to be nondefective is

Answer 1

Given 10 independent part,

No mean shift

This implies that,

The mean is 10

It also means that the variance is 0

And also the standard deviation is 0.

Then, the sigma deviation is

3×0+10=10.

Since none of the data is at such a high point, the manufacturing testing process has not yet reached three-sigma quality levels.

Since we have this let use the special consideration

Three-sigma limits set a range for the process parameter at 0.27% control limits. Three-sigma control limits are used to check data from a process and if it is within statistical control

Therefore,

The 0.27% will give the defective

2.7/100×10=0.027

Then, the none defective is

1-0.027=0.973

Which is 97.3%