Answer:
16
Step-by-step explanation:
The sample mean for machine #1 is obtained by simply adding up the four sampled units of output for the machine (17, 15, 15, 17) and then dividing the result by four:
[tex]m=\frac{17+15+15+17}{4}\\ m=16[/tex]
Therefore, the sample mean for machine #1 is 16.