Quality Auditor Certification Statistical Sampling 3

Question 1

In ANSI/ASQ Z1.4, what happens to the sampling plan when a lot is submitted under tightened inspection and a second lot is rejected?

Accepted Answer

Acceptance of product is discontinued until corrective action is taken

Answer

Under Z1.4, if five consecutive lots are rejected on tightened inspection, acceptance of the product must be discontinued.

Question 2

A quality engineer applies a hypergeometric distribution rather than a binomial distribution when sampling. This choice is most appropriate when:

Accepted Answer

The sample is a significant fraction of a finite population

Answer

The hypergeometric distribution applies when sampling without replacement from a finite population where the sample is a substantial fraction.

Question 3

Average Total Inspection (ATI) in acceptance sampling includes which components?

Accepted Answer

Sample items plus all items in rejected lots that are 100% inspected

Answer

ATI accounts for sample inspection plus the full 100% inspection of all rejected lots after they are screened.

Question 4

Which of the following best describes the Lot Tolerance Percent Defective (LTPD)?

Accepted Answer

The defect rate at which there is a 10% probability of acceptance (consumer's risk point)

Answer

LTPD is the defect level at which the probability of lot acceptance equals the consumer's risk (typically 10%).

Question 5

A double sampling plan with n1=50, c1=1, r1=4, n2=100, c2=3 means a lot is accepted outright if the first sample yields:

Accepted Answer

1 or fewer defectives

Answer

In a double sampling plan, the lot is accepted after the first sample if defectives found are ≤ c1 (1 in this case).

Quality Auditor Certification Practice Test