Business statistics

Question

Temperature is used to measure the output of a production process. When the process is in control, the mean of the process is mean = 133.7  and the standard deviation is = 0.7.

a. Construct an x¯ chart for this process if samples of size 5 are to be used (to 2 decimals).

UCL = ..........

LCL = ..............

Answer 1

UCL and LCL = mean +/- 3 standard deviations

UCL = mean + 3 standard deviations = 133.7 + 3 * 0.7 = 135.8

LCL = mean - 3 standard deviations = 133.7 - 3 * 0.7 = 131.6