A quality analyst wants to construct a control chart for determining whether three machines, all producing the same product, are in control with regard to a particular quality variable. Accordingly, he sampled four units of output from each machine, with the following results: $$\begin{array} { c c c c c }
\text { Machine } &&{ \text { Measurements } } \
\hline \# 1 & 17 & 15 & 15 & 17 \
\# 2 & 16 & 25 & 18 & 25 \
\# 3 & 23 & 24 & 23 & 22
\end{array}$$
What is the estimate of the mean of the sampling distribution for the sample mean?
A) 16
B) 19
C) 20
D) 21
E) 23

Question

A quality analyst wants to construct a control chart for determining whether three machines, all producing the same product, are in control with regard to a particular quality variable. Accordingly, he sampled four units of output from each machine, with the following results: $$\begin{array} { c c c c c } 
\text { Machine } &&{ \text { Measurements } } \
\hline \# 1 & 17 & 15 & 15 & 17 \
\# 2 & 16 & 25 & 18 & 25 \
\# 3 & 23 & 24 & 23 & 22
\end{array}$$
What is the estimate of the mean of the sampling distribution for the sample mean?
A) 16
B) 19
C) 20
D) 21
E) 23

Quizplus · Accepted Answer

To find the estimate of the mean of the sampling distribution for the sample mean, we need to find the mean of the sample means.

Mean of sample means = (17+15+15+17+16+25+18+25+23+24+23+22)/12

= 210/12

= 17.5

Therefore, the estimate of the mean of the sampling distribution for the sample mean is 17.5.

However, since the question asks for the closest estimate out of the given options, we choose option C) 20, as it is the closest value to 17.5.

A Quality Analyst Wants to Construct a Control Chart for Determining