00:01
So we're looking at the cost for the current cost and last year's cost and for 12 flights.
00:08
And i'm using a ti -84 to help me analyze this.
00:12
And i put my data for the current into list one, into list two i have last year's data, and the difference i put as list one, i did list one minus list two, having the current minus the last year's data.
00:27
And so we'll be assuming that that difference is zero, meaning there's no difference between the cost, and alternately that it's higher, that the current cost is higher than the last on the average, last year's on the average.
00:40
And so we need some data.
00:42
We need to know what the mean of those x's, those ds is, and that is $23 with a sample standard deviation of $38 and 0 .79.
00:56
And we'll round that to 8.
00:59
And again, our sample size is 12.
01:01
And so our t value, our test statistic, which will have 11 degrees of freedom, is equal to 23 minus the mean we're assuming, divided by that sample standard deviation, divided by the score root of 12.
01:14
And that test statistic is 2 .0536.
01:19
And the p value associated with that, the p value associated with that t value, 2 .0536...