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43 votes
Max makes three piles of cards, each consisting of only a Queen and a Jack. Lisa draws one card from each pile. What is the probability that Lisa draws two Queen and a Jack in any order? Make a tree diagram of all the choices

User Manivannan
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2 Answers

24 votes
24 votes
3/8 hope this helps
User Piers Myers
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13 votes
13 votes

Answer:

3/8

Explanation:

The probability of picking either a Queen or a Jack from each pile is always 1/2 (as there are only 2 cards).

There are only 3 ways in which Lisa can draw two Queens and a Jack:

Queen, Queen, Jack

Queen, Jack, Queen

Jack, Queen, Queen

The probability of each one happening is 1/8

This is because there is a 1/2 chance of picking a Queen or a Jack from each pile and to calculate the probability that Lisa will pick a Queen AND a Queen AND then a Jack (for example) you multiply the probabilities together:

1/2 x 1/2 x 1/2 = 1/8

This is the same for other examples and since there are only 3 ways that Lisa can draw two Queens and a Jack you multiply 1/8 by 3 (you add 1/8 together 3 times) to get 3/8

It can be represented on a tree diagram however I am not sure how I can show images/drawings on this

User Wujo
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