a. 25.2 years
b. Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion/probability
(±.025) and its Z score.
95% = mean ± Z SEm
SEm = SD/√n
SD = √variance
c. Same process with ±.005.
A sample of 65 night-school students' ages is obtained in order to estimate the mean age of night-school students. x bar = 25.2 years. The population variance is 28.
(a) Give a point estimate for ì. (Give your answer correct to one decimal place.)
Correct: Your answer is correct. .
(b) Find the 95% confidence interval for ì. (Give your answer correct to two decimal places.)
Lower Limit Incorrect: Your answer is incorrect. .
Upper Limit
(c) Find the 99% confidence interval for ì. (Give your answer correct to two decimal places.)
Lower Limit
Upper Limit
1 answer