If 2 cards from a standard deck are selected randomly, what is the probability that at least one king or at least 1 ace occurs? (There are 4 Aces, 4 kings and 52 total cards in a standard deck.)
There are three cases:
1 ace 1 king: 2*1/13*4/51=8/663
1 ace 1 other: 2*1/13*47/51=94/221
1 king 1 other: 2*1/13*47/51=94/221
so, adding the probabilities up, we have 8/663+282/663+282/663=572/663=44/51.
The chance of drawing an ace or a king ... I think 86% seems high.
I would have said the first card has an 8/52 chance.
If that card isn't an ace or a king, then the second card has an 8/51 chance.
Added together is 0.3107 ... 31% still seems high, but whatever.
