SOLUTION: I tried much in this problem but I didn't get my answer correct. The question is--- A person draws two cards successively without replacement from a pack of 52 playing cards.

Algebra ->  Probability-and-statistics -> SOLUTION: I tried much in this problem but I didn't get my answer correct. The question is--- A person draws two cards successively without replacement from a pack of 52 playing cards.      Log On


   



Question 1052489: I tried much in this problem but I didn't get my answer correct.
The question is---
A person draws two cards successively without replacement from a pack of 52 playing cards.He tells that both cards are aces,then the probability that both cards are aces if there are 60% chances that he speaks truth-----

Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
the probability of drawing an ace out of the deck the first time is 4/52.

the probability of drawing an ace out of the deck the second time without replacement is 3/51.

the assumption is that you got the ace the first time and there are only 3 aces left out of 51 cards left.

so the probability of drawing two aces out of the deck without replacement is 4/52 * 3/51.

if the person speaks the truth 60% of the time, than he actually has two aces 60% of the time.

if the person lies 40% of the time, than he actually doesn't have two aces 40% of the time.

so, 60% of the time, the probability that he actually has two aces is 4/52 * 3/51, and 40% of the time, the probability that he actually has two aces is 0.

the overall probability that he actually has 2 aces is therefore .60 * 4/52 * 3/51 + .40 * 0 which is equal to .60 * 4/52 * 3/51 which is equal to .0027149321.

in fractional form, this is equal to 3/1105.

this is what i think is happening.

try it out and see if it's right.