Probability= number of favorable outcomes
number of possible outcomes
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Is it better to play 50 dollars one week, or one dollar for fifty weeks?
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9­2: Tree Diagrams
Probability= number of favorable outcomes
number of possible outcomes
We must always find out how many possible outcomes there are!!!
One way to do so is to create tree diagrams.
For example...
If we were to flip a nickel and a dime, what is the probability that they are both heads?
Most people think the probability is 1/2, but they are wrong.
Let's find the number of favorable outcomes and the number of possible outcomes.
3
A card is picked then the spinner is spun.
1.) Draw the tree diagram.
2.) Show the sample space.
3.) How many possible outcomes are there?
4.) What is the probability of getting a red card and orange spun?
5.) What is the probability of getting a blue card then a purple or green spun?
4
A spinner is spun then the dice is rolled.
1.) Draw the tree diagram.
2.) Show the sample space.
3.) How many possible outcomes are there?
4.) What is the probability of getting a green then a six?
5.) What is the probability of getting an orange then an even number?
5
Two dice are rolled.
1.) Draw the tree diagram.
2.) Show the sample space.
3.) How many possible outcomes are there?
4.) What is the probability of getting Mr. Barclay then an "O"?
5.) What is the probability of getting a male teacher then a vowel?
6
Three coins are flipped.
1.) Draw the tree diagram.
2.) Show the sample space.
3.) How many possible outcomes are there?
4.) What is the probability of getting three heads?
5.) What is the probability of getting at least 1 head?
7
A coin is flipped and a dice is rolled.
1.) Draw the tree diagram.
2.) Show the sample space.
3.) How many possible outcomes are there?
4.) What is the probability of getting a head and 5?
5.) What is the probability of getting a tail then a number less than 3?
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