Which of the following is NOT a requirement for testing a claim about a standard deviation or variance? A. The sample is a simp
le random sample. B. The chi-square distribution is used. C. The population has a normal distribution. D. The population must be skewed to the right.
1 answer:
You might be interested in
Answer: The 95% confidence interval for the mean of x is (94.08, 101.92) .
Step-by-step explanation:
We are given that ,
A random variable x has a Normal distribution with an unknown mean and a standard deviation of 12.
i.e.
Also, it is given that , Sample mean having sample size : n= 36
For 95% confidence ,
Significance level :
By using the z-value table , the two-tailed critical value for 95% Confidence interval :
We know that the confidence interval for unknown population mean is given by :-
, where = Sample mean
= Population standard deviation
= Critical z-value.
Substitute all the given values, then the required confidence interval will be :
Therefore, the 95% confidence interval for the mean of x is (94.08, 101.92) .