The mathematical purpose of this lesson is for students to make sense of conditional probability, the relationship between conditional probabilities and the probability that two events both occur, and to use conditional probability to investigate independence. Students encounter the term conditional probability in this lesson which is defined as the probability that one event occurs under the condition that another event occurs. The work of this lesson connects to previous work because students use probability to investigate dependence and independence. The work of this lesson connects to upcoming work because students will create and use twoway tables to estimate conditional probabilities. When students do the same type of calculation several times and observe that \(P(\text{A and B}) = P(\text{A  B}) \cdot P(\text{B})\) for events A and B they are looking for and expressing regularity in repeated reasoning (MP8).
Lesson overview
 8.1 Warmup: She Made Some Tarts (5 minutes)
 8.2 Activity: Under One Condition (10 minutes)

8.3 Activity: Coin and Cube (15 minutes)
 Includes "Are you Ready for More?" extension problem
 Lesson Synthesis
 8.4 Cooldown: Soccer Games (5 minutes)
Learning goals:
 Comprehend (in written language) that the notation \(P(\text{A and B}) = P(\text{A  B}) \cdot P(\text{B})\) can be use to find the conditional probability for events A and B.
 Use conditional probability to justify (orally and in writing) that events are dependent or independent.
Learning goals (student facing):
 Let’s examine conditional probability.
Learning targets (student facing):
 I can estimate probabilities, including conditional probabilities, from twoway tables.
Glossary:
 Conditional Probability The probability that one event occurs under the condition that another event occurs.
 Access the complete Geometry Course Glossary.
Standards:
 This lesson builds towards the standard: CCSS.HSSCP.A.3MS.SCP.3MO.G.CP.A.3
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