Question

Listed below are the ages (in years) of a sample of randomly selected male movie stars. 32 32 33 25 21 29 38 32 33 23 27 45 52 29

(a) What is the sample size, the sample mean, and the sample standard deviation?

(b) Construct a 95% confidence interval for the mean age of all male movie stars.

(c) Write a sentence that interprets your confidence interval in the context of the question.

Answer 1

using excel>Addin>phstat>one sample tst

we have

Confidence Interval Estimate for the Mean
Data
Sample Standard Deviation	8.322153673
Sample Mean	32.21428571
Sample Size	14
Confidence Level	95%
Intermediate Calculations
Standard Error of the Mean	2.224189126
Degrees of Freedom	13
t Value	2.160368656
Interval Half Width	4.805068474
Confidence Interval
Interval Lower Limit	27.41
Interval Upper Limit	37.02

(a) the sample size is 13

the sample mean is 32.214 , and the sample standard deviation is 8.322

(b) the 95% confidence interval for the mean age of all-male movie stars is (27.41,37.02)

(c) we are 95% confident that the mean age of all-male movie stars lies in between (27.41,37.02)