The mean and variance of the data $$4,5,6,6,7,8, x, y$$, where $$x< y$$ are 6 and $$\frac{9}{4}$$, respectively. Then, $$x^2-2 y$$ is equal to

The mean of five observations is 4 and their variance is 5.2. If three of these observations are 1, 2 and 6, then the other two are

For a random variable X, E(X) = 3 and E(X²) = 11. The variable of X is :

The sum of 10 items is 12 and the sum of their squares is 18, then the standard deviation will be

The runs of two players for 10 innings each are as follows

The more consistent player is

The mean of five observation is 5 and their variance is 9.20. If three of the given five observation are 1, 3 and 8, then a ratio of other two observations is