The Mean of the Sample Means and the Pooled Standard $\bar{\bar { x } }= 150$

True/False

The mean of the sample means and the pooled standard deviation of 36 samples of size 9 taken from a production process under control are $\bar{\bar { x } }= 150$ ,and S = 6,respectively.The lower control limit of the 3-sigma $\bar { x }$ chart is 147.