The number of "near misses" recorded for the last 20 months at the Lima Intl Airport is 3,2,3,2,2,3,5,1,2,2,4,4,2,6,3,5,2,5,1, 3. Develop an appropriate control chart . Determine the mean number of misses per month and the limits on the number of misses per month.
Show all your work/calculations . Are their any months where the number of near misses is out of control?