00:02
Hello, so here we have our given information and then you realize that here we have the sample standard deviation.
00:11
So we will be using the t -distribution if the need arises.
00:16
So the first thing we need to look at here is to get our margin of error e.
00:24
There we will need our t -distribution or the critical t value times the standard deviation divided by square root of n.
00:34
Let's see how we can find the critical t value.
00:37
That is the t value at alpha over 2 and degree of freedom.
00:45
So let's first get our alpha value.
00:52
We use 1 minus the confidence level.
00:54
So we have 1 minus confidence level is 95 percent that's 0 .95.
01:00
We have 0 .05.
01:03
We divide this by 2, we get 0 .025.
01:07
Let's check our degree of freedom.
01:10
That's n minus 1.
01:14
So we're going to have 25 minus 1...