00:03
Hello, welcome to this lesson.
00:04
In this lesson, construct 99 % confidence interval for the data below.
00:12
We've been given a standard deviation of 4, so we have to find the mean of the data so that with the margin of error we can find the confidence interval.
00:24
So the first point is to find the point estimate which is w.
00:31
So we look at the mean of the data, that is the summation of all these data points divided by the number of the sample size.
00:48
So with this we have 65 .22 as the point estimate.
00:54
Okay, the second point is to look at the margin of error.
01:03
So the margin of error is calculated as the t -score.
01:12
Here we are using t -score because the sample size is 9.
01:15
This times the standard deviation all over the square root of the sample size.
01:27
So here we have the t -score or the critical value as 2 .896...