Pioneer Chicken advertises “lite” chicken with 30% fewer calories than standard chicken. When the process for “lite” chicken breast production is in control, the average chicken breast contains 420 calories, and the standard deviation in caloric content of the chicken breast population is 25 calories.
Pioneer wants to design an x-chart to monitor the caloric content of chicken breasts, where 25 chicken breasts would be chosen at random to form each sample.
(a) What are the lower and upper control limits for this chart if these limits arc chosen to be four standard deviations from the target?
(b) What are the limits with three standard deviations from the target?