Statistics
Probability

What probability draw 2 cards sum is 9?

Answer

Wiki User
01/17/2011

Assuming a standard deck of 52 cards with aces counting as 1 and all face cards counting as 10, there are:

16 ways of drawing an ace and an 8,

16 ways of drawing a 2 and a 7

16 ways of drawing a 3 and a 6

16 ways of drawing a 4 and a 5, for a total of 64 ways to draw 2 cards whose sum is 9.

There are 52!/(50!2!) = 1,326 ways to draw two cards, so the probability is 64/1326 = 0.048, or about 1 in 21.