Computer chip manufacturing. MediaChip manufactures computer chips specifically for MP3 players. The process uses sophisticated lasers to imprint several hundred chips on a single silicon “wafer.” While the process is completely automated and set in a clean room environment, a batch of chips can contain imperfections that render the chips useless.

This results in significant cost overruns. MediaChip would like to use a control chart to monitor their manufacturing process. Presently, the production level is set to 250 wafers per day. The average number of defects that can be tolerated is 1.7 per day. The number of defective wafers was tracked and recorded in the following table.

Day Defects Day Defects 1 1 11 3 2 1 12 3 3 2 13 2 4 0 14 2 5 2 15 1 6 2 16 2 7 2 17 1 8 3 18 2 9 2 19 2 10 2 20 1

a) Create a c chart.

b) Is MediaChip’s manufacturing process in control?