Thread: Probability question...

Suppose the two joker cards are left in a standard deck of cards. One joker is red and the other is black. A single card is drawn from the deck of 54 cards but not returned to the deck, and the second card is drawn. Determine the probability of drawing a red joker or a red ace on either draw.

1/54 chance for the red joker.

2/54 chance for the red ace.

Thats all I can come up with ,don't know how to finish it.

There are 3 total red jokers and red aces in the deck of 54 cards. If you mean the probability of drwaing at least 1 of them then you look at the 3 possible cases. Draw a red on first but not second, draw a red on second but not first, and draw a red on both.

Draw a red on first but not second = (3/54)(51/53)
Draw a red on second but not first = (51/54)(3/53)
Draw a red on both = (3/54)(2/53)'

Then you add them all up = (153+153+6)/(54)(53) = 312/2862 = 52/477, or about .109.

thanks.

Originally Posted by Skoz

Suppose the two joker cards are left in the standard deck of cards. One of the jokers is red and the other is black. A single card is drawn from the deck of 54 cards, returned and then a second card is drawn. Determine the probability of drawing.

f) The red joker or a red ace on either draw.

1/54 chance for the red joker.

2/54 chance for the red ace.

Thats all I can come up with ,don't know how to finish it.

1 - Pr(no red joker or red ace on either draw) = 1 - (51/54)^2.

A tree diagram makes this clear.