Two cards are drawn simultaneously (or successively without replacement) from a well shuffled pack of 52 cards. Find the mean, variance and standard deviation of the number of kings.

Explanation

It is known that there are `52` cards in a deck of cards and there are `4` kings in total.

This means that there are `48` non-king cards.

Let us suppose that `X` denotes the number of kings in a draw of two cards.

Then, there arise the following three cases,

there is no king, i.e., `X=0`

there is one king, i.e., `X=1`

there are two kings, i.e., `X=2`

Now, the probability that there is no king in a simultaneous draw of two cards is,

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