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tree diagram

E-Math: Interesting Probability Math Teaser (Plus usage of Tree Diagram)

You are a prisoner sentenced to death. The Emperor offers you a chance to live by playing a simple game. He gives you 50 black marbles, 50 white marbles and 2 empty bowls. He then says, "Divide these 100 marbles into these 2 bowls. You can divide them any way you like as long as you use all the marbles. Then I will blindfold you and mix the bowls around. You then can choose one bowl and remove ONE marble. If the marble is WHITE you will live, but if the marble is BLACK... you will die."

How do you divide the marbles up so that you have the greatest probability of choosing a WHITE marble?

Do you know how? ;) Leave your answer in the comment section. I will reveal the answer if anyone is interested to know.

In E-Math, we discussed about probability on possibility diagram, tree diagram, mutually exclusive events, independent events. Fortunately we do not go into permutation and combination where things get slightly more exciting.

Do you use more of tree  or possibility diagram  to help you in your probability question?

I'm going to show you an example of modified tree diagram to solve the following question

Bag A contains 15 bronze rings, 6 silver rings and 4 gold rings. Three rings are drawn at random, one after the other without replacement from bag A.

Calculate the probability of not drawing any gold ring.

modified-tree-diagram

Additional question: Calculate the probability of drawing all three rings that are different.

Filed Under: E-Maths Tagged With: probability, tree diagram

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