Question

Problem 10-30 In the past, Alpha Corporation has not performed incoming quality control inspections but has taken the word of its vendors. However, Alpha has been having some unsatisfactory experience recently with the quality of purchased items and wants to set up sampling plans for the receiving department to use For a particular component, X. Alpha has a lot tolerance percentage defective of 47 percent. Zenon Corporation, from which Alpha purchases this component, has an acceptable quality level in its production facility of 16 percent for component X. Alpha has a consumer's risk of 10 percent and Zenon has a producer's risk of 5 percent. Use Exhibit 10.16 a. When a shipment of Product X is received from Zenon Corporation, what sample size should the receiving department test? (Round up your answer to the next whole number.) Sample size b. What is the allowable number of defects in order to accept the shipment? Allowable number of defects

Answer 1

AQL = 0.16
LTPD = 0.47

LTPD / AQL = 0.47 / 0.16 = 2.94

c n*AQL 2.613 ת 3.286 6 77 LTPD/AQL 3.549 3.206 12.957 2.768 2.618 13.981 8 4.695 9 5.426

From the table, the nearest value of LTPD / AQL is 2.957

So,

(a)

n * AQL = 3.981

or, n = 3.981 / AQL = 3.981/0.16 = 24.88

So, the sample size is 25

(b)

Acceptance number or the number of detectives up to which the lot is accepted = c = 7