Thread: conditional probability

hi,can anyone pls help.thx!!

a friend randomly chooses 2 cards,without replacement, from an ordinary deck of 52 cards.determine the conditional probability that both cards are aces if you ask your friend if either of the cards selected is an ace and your friend said yes.

are you asking P(both are aces|at least one is an ace)?

If so, just use

Let A=both are aces

B=at least one is an ace

AB=A so P(AB)=P(A)= (4/52)(3/51)

while P(B)=1-P(No aces)=1-(48/52)(47/51)

Yups

done