Answer:
Mean of sampling distribution = 25 inches
Standard deviation of sampling distribution = 4 inches
Step-by-step explanation:
We are given the following information in the question:
Mean, μ = 25 inches
Standard Deviation, σ = 12 inches
Sample size, n = 9
We are given that the distribution of length of the widgets is a bell shaped distribution that is a normal distribution.
a) Mean of the sampling distribution
The best approximator for the mean of the sampling distribution is the population mean itself.
Thus, we can write:
b) Standard deviation of the sampling distribution
9514 1404 393
Answer:
B
Step-by-step explanation:
When solving multiple choice problems, a reasonable strategy is to look for ways to identify one answer as good, or other answers as bad.
Here, all of the constant vectors in the equations are different, so we can decide the answer based on that.
The only equation with the correct constant vector is choice B.
_____
The constants in the equations are -4, 1, 9 — the values to the right of the equal sign.