Q1) Wolfcon, a Chinese manufacturer, assembles smartphones. Microprocessor chips in these products are purchased in batches from an outside vendor.

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  

                                                                                     [30%]

(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.

                                                                                                                  [60%]

(c) What is the probability of acceptance if the batch percent defective is 3.5%?        

[10%]