Q1) Wolfcon, a Chinese manufacturer, assembles smartphones. Microprocessor chips in these products are purchased in batches from an outside vendor. This vendor produces the chips to an AQL of 2% defective and is prepared to take a 5% risk (Producer Risk, α) of having lots of this level or fewer defectives rejected. Wolfcon considers batches of 8% or more defectives unacceptable (the LTPD) and wants to ensure that it will accept such batches no more than 10% of the time (Consumer Risk, β). The sampling plan is c = 4, n = 99.
(a) Sketch a graph to show AQL, Producer Risk, Consumer Risk and LTPD for this sampling scheme
(b) Calculate and tabulate at least five acceptance probabilities for different percentages defective. Using this data draw on graph paper the operating characteristic of this sampling scheme.
(c) What is the probability of acceptance if the batch percent defective is 3.5%?