00:01
Alright, so our null hypothesis is going to be that the means are equivalent to each other, and the alternative hypothesis is that the mean of one is going to be greater than the mean of two.
00:14
So, defining our test statistic, we're going to have x bar one, which is 2 .7, minus x bar two, which is 2 .3, over the standard deviation, or over the square root of the standard deviation of one, or the variance of one, which is 0 .8 squared over n one, plus the variance of two, which is 0 .5 squared over n two.
00:42
So let's toss that into a calculator.
00:45
That's going to be 0 .4 over the square root of 0 .8 squared divided by 11, plus 0 .5 squared divided by 11, and we'll end up with 1 .406.
01:03
So let's find our t critical value.
01:06
So our alpha level is 0 .1, and our degrees of freedom is going to be n one plus n two minus two.
01:16
So that's 22 minus two, so 20.
01:18
So let's find our t critical value there, and we should end up with our critical value being 1 .72...