Correct question is;
Rosters 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 450 calories, and the standard deviation in caloric content of the chicken breast population is 20 calories. Rosters 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 are chosen to be four standard deviations from the target? b) What are the limits with three standard deviations from the target? Upper Control Limit (UCL)calories (enter your response as an integer).
Answer:
A)UCL = 466
LCL = 434
B)UCL = 462
LCL = 438
Explanation:
We are given;
Mean;μ = 450
Standard deviation; σ = 20
Sample size; n = 25
A) We are told that these limits are chosen to be four standard deviations from the target.. This means that z-value = 4.
Thus, upper control limit will be the formula;
UCL = μ + 4σ/√n
UCL = 450 + 4(20)/√25
UCL = 450 + 16
UCL = 466
Lower control limit will be;
LCL = μ - 4σ/√n
LCL = 450 - 4(20)/√25
LCL = 450 - 16
LCL = 434
B) We are now told that these limits are chosen to be three standard deviations from the target.
Thus, z = 3
So;
UCL = μ + 3σ/√n
UCL = 450 + 3(20)/√25
UCL = 450 + 12
UCL = 462
Lower control limit will be;
LCL = μ - 3σ/√n
LCL = 450 - 3(20)/√25
LCL = 450 - 12
LCL = 438