00:01
Hi, i'm david and i'm here to have you and answer your question.
00:03
Now in this question here we are going to discuss about the central limit theorem.
00:10
We know that if we have the same size n greater equal to the 30, and then the symbol mean x -bar will be approximately to the normal.
00:17
In such a way that if we've obtained the x -bar, we minus the mean of a standard division, divided by square of n, we obtain the standard normal.
00:24
Here we have the two scenarios and we split the screen onto the two parts.
00:29
The function with the pay time and the second one will be the unpaid time now for the pay time we have the x will follow by the normal it will be it's not the normal so we just follow some distribution with the mean equal to the 1 .3 and the sigma equal to no 1 .9 and found the unpaid the x will follow some description with the mean equal to the 1 .4 and the sigma equal to the 1 .8 and both of them they use the same symbol and equal to 100.
01:23
Now for the question a, our condition will be the a.
01:28
So first of of all we need to identify the mean of the x bar which equal to the mu and we each to equal to the 1 .3.
01:35
Standard division of x bar equal to the sigma a plus greater the n equal to 1 .9 squared the 100 equals 0 .19.
01:48
And the question asks me to find the probability of the x -par greater than the 1 .5.
01:54
To find this probability, i need to convert the x -par into the z.
01:58
To do it, i need to apply this formula here.
02:00
And then i will have the 1 .5 and minus the mean will be the 1 .3 of the standard deviation...