OC Curve Calculation
A muffler shop just received a shipment of 1000 mufflers. The sampling plan calls for a sample
size of 60 and an acceptance target of one. The contract with their supplier specifies an AQL of
1 defect per 100 mufflers and an LTPD of 6 defects per 100 mufflers. They would like the plan
to yield an of and a of . Calculate the probability of acceptance (Pa) over the range
of [0, ]. Does this plan meet the requirements for and ?
p np Pa
()(60) =
()(60) =
()(60) =
()(60) =
()(60) =
()(60) =
()(60) =
()(60) =
()(60) =
()(60) =
()(60) =
Table 1. Probability of Acceptance
= 1 – Pa at AQL
= Pa at LTPD
Changes in the OC Curve
Increase n and keep c constant Increase c and keep n constant
N c
60 1
80 2
100 3
120 4
Average Outgoing Quality
p np Pa AOQ
()(60) =
()(60) =
()(60) =
()(60) =
()(60) =
()(60) =
()(60) =
()(60) =
Table 2. AOQ
