You select 3 cards without replacement from a deck of 52 cards. Calculate the
probability that the first card picked was an ace conditional on the fact that the last two were Jacks. Note that here you need to assume that you are drawing the cards out sequentially .
I think I need to do:
P(Ace|Jacks) = (P(Ace ∩ Jacks)) / P(Jacks)
But I have hard time to find (P(Ace ∩ Jacks)) and P(Jacks). Can anyone explain this for me?
Thanks!
Best Answer
An alternate approach:
Reason that the probability that first is ace given second two are jacks is the same as the probability that the third is an ace given the first two are jacks.
Further reason that the probability is the same as the probability of drawing an ace from a deck of 50 cards, four of which are aces.
The probability is then $\frac{4}{50}=\frac{2}{25}=0.08$