00:01
So we're looking at a frequency distribution, and so the first thing in order to calculate that mean, we need to have the midpoint of each of these.
00:10
So basically add these together and divide by 2, or you can see that the middle will end up being 11, 14, 17, 20, and 23.
00:18
Now the mean will end up being, or the expected value of the time is going to be that 11 times 3 plus the 14 times 12, all the way up to that 23 times 2, and add up all of those values and divide by how many we have.
00:35
And that mean comes out to be 17 .5357.
00:42
And if we wanted to discuss the, it says compute the first four moments about the mean, and so i'm calculating the mean, and i don't know what it means to have those moments, so unless you mean to go out a standard deviation.
01:06
So if we found the standard deviation of these values, that would come out to be approximately 3, 2 .9785.
01:17
So basically the distribution is centered if we look at a picture of the graph, and i'm just going to go to 11, 14, 17, 20, 23, and show it this way...