Lesson 7
Related Events
Lesson Narrative
The mathematical purpose of this lesson is for students to understand the difference between independent and dependent events in terms of probability. Students encounter the term independent events which is defined as two events from the same experiment for which the probability of one event is not affected by whether the other event occurs or not, and the term dependent events which is defined as two events from the same experiment for which the probability of one event depends on the result of the other event. The work of this lesson connects to previous work because students applied the addition rule to solve problems. The work of this lesson connects to upcoming work because students will solve problems involving conditional probability. When students use probability to analyze a situation to determine whether or not the events are dependent or independent they are looking for and making use of structure (MP2).
Learning Goals
Teacher Facing
 Comprehend (in spoken and written language) the term independent events refers to the probability of one event being impacted by the occurrence of the other event.
 Use the concept of probability to justify (in writing) whether two events are independent or dependent. Generate (in writing) examples of experiments involving independent and dependent events.
Student Facing
 Let’s see how events are related.
Required Materials
Learning Targets
Student Facing
 I can estimate probabilities, including conditional probabilities, from twoway tables.
CCSS Standards
Glossary Entries

dependent events
Dependent events are two events from the same experiment for which the probability of one event depends on whether the other event happens.

independent events
Independent events are two events from the same experiment for which the probability of one event is not affected by whether the other event occurs or not.