Three numbers are selected at random (without replacement ) from first six positive integers. Let X denote the largest of the three numbers obtained. Find the probability distribution of X. Also, find the mean and variance of the distribution.
As the first 6 positive integers are 1,2,3,4,5,6 so the variate X takes values 3,4,5 and 6. The probability distribution is given as :
X | 3 | 4 | 5 | 6 |
P(X) |
Now the mean of the distribution
Variance of the distriburtion =