00:01
Welcome students, given that a fair coin is stars to 25 times.
00:24
The probability distribution for the number of heads x is given.
00:32
The probability distribution for the number of heads x is given.
00:50
So here we have to find the mean and standard deviation using excel.
00:55
If p of x be the probability distribution if p of x be the probability distribution of a random variable x here the formula for mean and a standard deviation is mean is equals to that is e x is sigma x multiplied by p of x x sigma x multiplied by p of x variance is e x square minus e of x whole square standard deviation is is equal to under root of variance under root of variance this is the excel sheet of probability distribution of random variable x.
03:05
Here the variable x is given.
03:09
P of x is a probability distribution of variable x and x multiplied by px and x squared multiplied by px.
03:21
So the sum of x multiplied by px is 12 .5 and the sum of x multiplied by px is 12 .5 and the sum of x squared multiplied by px is 162 .5076.
03:31
So the sum of x multiplied by px is nothing but the mean.
03:36
So here mean is equal to 12 .5.
03:47
Variance is equal to is equal to ex square minus e of x whole square.
04:04
So, ex square is sum of x squared multiplied by p of x minus ex whole square is sum of x multiplied by p of x whole square...