00:01
So in this question we want to test using a level significance equals to one percent if the cars that are equipped with radial tires have a higher average fuel basically have on average a better fuel economy than those with the other type of tires.
00:26
So so basically what we are testing is if on average those with the radial type has a higher fuel economy than those with the doubted type.
00:42
So that's what we want to test.
00:44
So this is our alternative hypothesis because it does not include the equal sign, which means that our new hypothesis will be the opposite of this claim, which will include the equal sign.
00:55
So to pass this we need to compute the difference between or we can rewrite this to be the difference between the two averages so we can rewrite this to be that these averages less or equal than zero or higher than zero so to pass this considering that we all have a tuple in this case that we have this this pairing factor here, what we're going to do is we're going to compute using the data that we have here, what is the difference between the radial tire with respect to the belted tire.
01:40
So this is the same as computing for each car, 4 .8 minus 4 .6, and we do this until we reach the tenth car which is also 4 .8 minus 4 .3 so in this case what we're gonna get is 0 .2 so this one's 0 .5 but for example car number two we get a difference equals to negative zero four so what we need to do is we need to add these numbers together so we need to have here what is the sum of these differences here to get the average later.
02:21
So the sum of this difference will be in this case equals to 0 .9, which means that the average that we have for the differences here will be 0 .09...