The mean of the sample means and the pooled standard deviation of 25 samples of size 4 taken from a production process under control are found to be 150 and 10,respectively.The centerline for the chart is:
A)150
B)100
C)250

Question

The mean of the sample means and the pooled standard deviation of 25 samples of size 4 taken from a production process under control are found to be 150 and 10,respectively.The centerline for the  chart is:
A)150 
B)100 
C)250

Quizplus · Accepted Answer

The centerline for the 11ea78b9_2e5f_1f3c_8379_ab0f9dbf4b26_TB4388_11 chart is equal to the overall mean of the sample means. Here, the mean of the sample means is given as 150. Therefore, the correct answer is A) 150.

The Mean of the Sample Means and the Pooled Standard