00:01
So let us start with the concept which we are going to use here for this question.
00:09
So we have to use z -score formula which should be equal to x bar minus mu by sigma by undoubted of n where mu is the mean, sigma is standard deviation and sample size and x bar is the population mean or sample mean you can say and mu is the population mean here.
00:29
While the degree of freedom they should be equals to n minus of 1.
00:35
Now what is the concept we are going to have? if z calculated will be greater than equals to the z tabulated means the critical the null half thesis is rejected.
00:50
Null half thesis is rejected.
00:54
This is what the simple concept we want to use.
00:57
So, let us get started with solution.
00:59
So, in a part, first of all, we have to set the null hypothesis.
01:04
H0 mu is equal to 3.
01:07
And alternative hypothesis will be mu less than to 3.
01:11
Means we have to perform the left -tailed test.
01:15
Now, in b part, for the 95 % of confidence, our significance level should be 0 .05.
01:24
So, let us calculate z of 0 .05 means critical value.
01:30
So, this will comes out negative of 1 .64 pipe from the z table.
01:37
So, basically this is two tailed test by critical value...