Question

Will someone help me solve this?

sally was given a standard deck of 52 cards she randomly chose 3 cards from the deck replacing the card befor each time. what is the probability of choosing an ace, a queen, and a six?

Answer 1

Since Sally replaces the card after each draw, there are 52 choices for each card that can be drawn.

In a standard deck of cards, there are 4 aces. Then the probability of drawing an ace is 4/52 = 1/13. The same reasoning applies to drawing a queen or a six. Then the probability of drawing an ace, queen, and six (in that particular order) is 1/13³.

But Sally can also draw these 3 specific cards in any order to end up with the same hand. There are 3! = 6 ways of doing so:

AQ6, A6Q, QA6, Q6A, 6AQ, 6QA

That is, 3 choices for the first card; 2 choices for the second; and 1 for the third, so a total of 3 • 2 • 1 = 3! = 6 hands.

Then the probability of getting a hand consisting of an ace, queen, and six is

3! • 1/13³ = 6/2197 ≈ 0.002731