Two cards are drawn simultaneously (without replacement) from a well-shuffled pack of 52 cards. Find the mean and variance of the number of red cards.

Explanation

There can be three cases here.

`Case 1 :` When both drawn cards are not red.

Then, both cards will be black.

Then, `P(r=0) = 26/52**25/51`

`Case 2 :` When one of the drawn card is red and other is black.

In this case, either first card is red or second card is red.

So, `P(r=1) = 26/52**26/51+26/52**26/51 = 2(26/52**26/51)`

`Case 3 :` When both drawn cards are red.

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