Question

When a process is in control, it results in there being, on average, 16 defects per unit of output. c-chart limits of 4 and 28 would lead to a ________ percent chance of a Type I error.

Answer 1

Answer:

Type 1= 0.3 %

Explanation:

This is a 3 sigma limit given by ( μ±3σ) . Chebyshev's inequality states that at least 89% of the observations fall in the three sigma limits ( μ±3σ) . The probability increases towards 99.7% as the distribution becomes normal.

Normal distribution= 99.7% observations fall within μ ± 3σ

Type 1 Error= (100- 99.7)%= 0.3%

Upper control limit = UCL= μ + 3σ

Lower control limit = LCL= μ - 3σ