00:03
In this problem, you're being asked to construct the indicated confidence interval for a population mean mu using the t distribution.
00:13
And so the important thing to keep in mind here is that we're working with a t distribution.
00:19
And to recap, in such a distribution, we don't know the population standard deviation sigma.
00:31
And so as such, the steps for figuring out the confidence level from a t distribution is first.
00:38
To find a t -value, later to find using this, the margin of error, which finally you can use to find the confidence interval.
01:06
Now to start off the problem, you're given a few things.
01:09
So first, you know that the confidence interval is equal to 0 .98, or the confidence level is equal to 0 .98.
01:17
You're given x bar the mean, and this is equal to 4 .3.
01:21
You also know the sample standard deviation, again, not the population, but the sample, which is 0 .34.
01:29
And finally, you know the sample size is 14.
01:33
And to first determine the t value, we need to know two things.
01:38
You need to know the competence level, which we are given, and we need to find the degrees of freedom...