00:01
In this question we have been able that is x 3, 4 and 5.
00:06
And probability of x is given as 0 .36, 0 .43 and 0 .21.
00:15
Now we have to calculate the variance.
00:18
So for finding variance, first we have to find the value of mean, that is mu or you can say e of x and after that we can find the value of variance.
00:29
So, here the next column can be written as x multiplied with p of x.
00:37
So 3 multiplied with 0 .36 will give you 1 .3 to 8.
00:43
4 multiplied with 0 .43 is 1 .72.
00:48
5 multiplied with 0 .21 is 1 .26.
00:53
Now, we know the formula for finding population mean, that is mu is 7 .26.
01:01
Equals to summation x i multiplied with p of x i where i is running from 1 to n so here we have this value obtained as well some x multiplied with p of x so we need to just add this value so mu is equal to 1 .08 plus 1 .72 plus 1 .26 so it implies mu is equal to 4 .06 now to the next part we have to find the variance of x so variance of x is given as e of x square minus e of x the whole square so first we have to find this e of x square so for that here we will add another column that is x squared multiplied with p of x so this is equals to 9 multiplied with 0 .36 that is equal to 3 .24 here, 16 multiplied with 0 .43, that will give us 6 .88.
02:12
Tier 25 multiplied with 0 .21 results into 7 .56.
02:20
Now, first we'll calculate e of x square...