Statistics and Probability / Probability Diagrams and Tables

Understanding

The probability of a compound event can be found by listing the outcomes for one event followed by the other, creating a probability tree, or by using the product rule for independent events.

What to look for

Students should understand when it is appropriate to multiply the probabilities of individual outcomes in order to determine the probability of a compound event.

Sample Assessment

A nickel, a dime, and a quarter are flipped at the same time. Each coin can land either heads up (H) or tails up (T). List all the different possible outcomes for this event in the chart below. The list has been started for you.

Answer: 

The Big Idea

The probability of a compound event can be found by listing the outcomes for one event followed by the other, creating a probability tree, or by using the product rule for independent events.

What are the students doing?

Students highlight the branches that represent given situations in order to determine the probability of a compound event.

What is the teacher doing?

Be sure students understand how to represent numerically the probabilities of equally likely events and that the sum of the probabilities of all the outcomes for a certain event is always equal to 1.