MA.912.DP.4.6

Recognize and explain the concepts of conditional probability and independence in everyday language and everyday situations.
General Information
Subject Area: Mathematics (B.E.S.T.)
Grade: 912
Strand: Data Analysis and Probability
Date Adopted or Revised: 08/20
Status: State Board Approved

Benchmark Instructional Guide

Connecting Benchmarks/Horizontal Alignment

 

Terms from the K-12 Glossary

 

Vertical Alignment

Previous Benchmarks 

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Purpose and Instructional Strategies

In Algebra I, students studied associations in bivariate categorical data using conditional relative frequencies. In Math for College Liberal Arts, students work in more depth with conditional probabilities and independence in real-world contexts. 
  • Instruction includes tasks asking students to explain the meaning of independence in a simple context, as well as what it would mean for two events to not be independent. Students should analyze and think critically about relationships between two events that may or may not appear to be related. 
  • Provide common examples of independent and dependent events and ask students to provide examples of their own for both cases. 
    • Independent: Lisa ate breakfast, and she went to school.
    • Dependent: Jim loaded his videogame disk, and started playing his videogame. 
  • Remind students that given data, independence can be calculated, or verified. In some cases, situations that intuitively seem independent, may be correlated. Emphasize that this correlation does not imply cause or dependence, but rather only shows that the two events are not independent. (Refer to MA.912.DP.1.3 from Algebra I.) Two-way tables can be used to assist with this discussion. 
    • For example, ask students to answer a series of questions based on given data. The table below shows caffeine preference for mathematics and engineering students based on a survey of 200 college students.
      Table
      Students can describe two conditional probabilities in everyday language that can be determined from the “Mathematics” row in the table. Everyday language could include the probability of choosing a student who prefers coffee given they are math major; or of those who are math majors choosing an energy drinker. Students can describe two conditional probabilities in everyday language that can be determined from the “Coffee” column in the table. Everyday language could include the probability of choosing a student who is a math major given they drink coffee; or the probability of choosing an engineering student from the coffee drinkers.
      Students can determine whether students with a mathematics major more likely to drink coffee or if students with an engineering major are. To do so, students would need to determine if the events are independent (MA.912.DP.4.4). 
  • Students use their prior knowledge of the word independent to mean not relying on another, and believe that conditional probabilities should be different when events are independent. Emphasize that having equivalent conditional probabilities means the probability of an event is the same no matter whether the other event occurs.

 

Common Misconceptions or Errors

  • Students misinterpret the word independence in relation to probability. 
  • Students may believe equal conditional probabilities means two events depend on each other in order to be the same. To address this misconception, discuss the meaning in context to emphasize the probability of one event is just as likely whether the other event occurs or not. 
  • Students may assume independence based on the description of the events alone.

 

Instructional Tasks

Instructional Task 1 (MTR.7.1)  
  • One hundred people were surveyed and asked their preference for watching movies via streaming services or a movie theater. The results are shown in the table below. 

    • Part A. Describe three possible conditional probabilities using everyday language given this table. 
    • Part B. Find the probability that a person surveyed prefers streaming. 
    • Part C. Find the probability that a person surveyed prefers streaming given they are a child. 
    • Part D. Are the events of prefers streaming and being a child independent? Explain.

 

Instructional Items

Instructional Item 1 
  • Part A. Today there is a 55% chance of rain, a 20% chance of lightning, and a 15% chance of lightning and rain together. Are the two events “rain today” and “lightning today” independent events? Justify your answer. 
  • Part B. Now suppose that today there is a 60% chance of rain, a 15% chance of lightning, and a 20% chance of lightning if it’s raining. What is the chance of both rain and lightning today? 
*The strategies, tasks and items included in the B1G-M are examples and should not be considered comprehensive.

Related Courses

This benchmark is part of these courses.
1210300: Probability and Statistics Honors (Specifically in versions: 2014 - 2015, 2015 - 2019, 2019 - 2022, 2022 - 2024, 2024 and beyond (current))
7912070: Access Mathematics for Liberal Arts (Specifically in versions: 2014 - 2015, 2015 - 2018, 2018 - 2019, 2019 - 2022, 2022 - 2023, 2023 and beyond (current))
1210305: Mathematics for College Statistics (Specifically in versions: 2022 - 2024, 2024 and beyond (current))
1207350: Mathematics for College Liberal Arts (Specifically in versions: 2022 - 2024, 2024 and beyond (current))

Related Access Points

Alternate version of this benchmark for students with significant cognitive disabilities.
MA.912.DP.4.AP.6: Recognize the concept of independence in everyday situations.

Related Resources

Vetted resources educators can use to teach the concepts and skills in this benchmark.

Lesson Plans

Casino Royale:

Students examine games of chance to determine the difference between dependent and independent conditional probability.

Type: Lesson Plan

How to Hit it Big in the Lottery - Probability of Compound Events:

Students will explore a wide variety of interesting situations involving probability of compound events. Students will learn about independent and dependent events and their related probabilities.

Lesson includes:

  • Bell-work that reviews prerequisite knowledge
  • Directions for a great In-Your-Seat Game that serves as an interest builder/introduction
  • Vocabulary
  • Built-in Kagan Engagement ideas
  • An actual lottery activity for real-life application

Type: Lesson Plan

Proposed Budgets:

In this Model Eliciting Activity (MEA), students will analyze federal budget data to propose strategic allocations using mathematical skills like expected value calculations and data normalization to justify their recommendations.

Model Eliciting Activities, MEAs, are open-ended, interdisciplinary problem-solving activities that are meant to reveal students’ thinking about the concepts embedded in realistic situations. MEAs resemble engineering problems and encourage students to create solutions in the form of mathematical and scientific models. Students work in teams to apply their knowledge of science and mathematics to solve an open-ended problem while considering constraints and tradeoffs. Students integrate their ELA skills into MEAs as they are asked to clearly document their thought processes. MEAs follow a problem-based, student-centered approach to learning, where students are encouraged to grapple with the problem while the teacher acts as a facilitator. To learn more about MEAs visit: https://www.cpalms.org/cpalms/mea.aspx

Type: Lesson Plan

Modeling Conditional Probabilities 1: Lucky Dip:

This lesson unit is intended to help you assess how well students are able to understand conditional probability, represent events as a subset of a sample space using tables and tree diagrams, and communicate their reasoning clearly.

Type: Lesson Plan

Perspectives Video: Expert

Let's Make a Math Deal:

Should I keep my choice or switch? Learn more about the origins and probability behind the Monty Hall door picking dilemma and how Game Theory and strategy effect the probability.

Download the CPALMS Perspectives video student note taking guide.

Type: Perspectives Video: Expert

Problem-Solving Tasks

Rain and Lightning:

This problem solving task challenges students to determine if two weather events are independent, and use that conclusion to find the probability of having similar weather events under certain conditions.

Type: Problem-Solving Task

Alex, Mel, and Chelsea Play a Game:

This task combines the concept of independent events with computational tools for counting combinations, requiring fluent understanding of probability in a series of independent events.

Type: Problem-Solving Task

Breakfast Before School:

The purpose of this task is to assess a student's ability to explain the meaning of independence in a simple context.

Type: Problem-Solving Task

The Titanic 2:

This task lets students explore the concepts of probability as a fraction of outcomes using two-way tables.

Type: Problem-Solving Task

The Titanic 3:

This problem solving task asks students to determine probabilities and draw conclusions about the survival rates on the Titanic using a table of data.

Type: Problem-Solving Task

Text Resources

The Logic of Drug Testing:

This informational text resource is intended to support reading in the content area. This article explores the reliability of drug tests for athletes, using mathematics. The author attempts to address this issue by relating drug tests to conditional probability. Throughout the text, various numbers that affect the calculation of a reliable probability are discussed. Numbers such as test sensitivity, test specificity, and weight of evidence are related to Bayes' theorem, which is ultimately used to calculate the conditional probability.

Type: Text Resource

Understanding Uncertainty: What Was the Probability of Obama Winning?:

This informational text resource is intended to support reading in the content area. The article examines various factors that changed the uncertainty of whether Barack Obama would win the 2008 election. Specifically,the article discusses probability, the science of quantifying uncertainty. The article questions common methods for assessing probability where symmetrical outcomes are assumed. Finally, the author explains how to use past evidence to assess the chances of future events.

Type: Text Resource

STEM Lessons - Model Eliciting Activity

Proposed Budgets:

In this Model Eliciting Activity (MEA), students will analyze federal budget data to propose strategic allocations using mathematical skills like expected value calculations and data normalization to justify their recommendations.

Model Eliciting Activities, MEAs, are open-ended, interdisciplinary problem-solving activities that are meant to reveal students’ thinking about the concepts embedded in realistic situations. MEAs resemble engineering problems and encourage students to create solutions in the form of mathematical and scientific models. Students work in teams to apply their knowledge of science and mathematics to solve an open-ended problem while considering constraints and tradeoffs. Students integrate their ELA skills into MEAs as they are asked to clearly document their thought processes. MEAs follow a problem-based, student-centered approach to learning, where students are encouraged to grapple with the problem while the teacher acts as a facilitator. To learn more about MEAs visit: https://www.cpalms.org/cpalms/mea.aspx

Student Resources

Vetted resources students can use to learn the concepts and skills in this benchmark.

Problem-Solving Tasks

Rain and Lightning:

This problem solving task challenges students to determine if two weather events are independent, and use that conclusion to find the probability of having similar weather events under certain conditions.

Type: Problem-Solving Task

Alex, Mel, and Chelsea Play a Game:

This task combines the concept of independent events with computational tools for counting combinations, requiring fluent understanding of probability in a series of independent events.

Type: Problem-Solving Task

Breakfast Before School:

The purpose of this task is to assess a student's ability to explain the meaning of independence in a simple context.

Type: Problem-Solving Task

The Titanic 2:

This task lets students explore the concepts of probability as a fraction of outcomes using two-way tables.

Type: Problem-Solving Task

The Titanic 3:

This problem solving task asks students to determine probabilities and draw conclusions about the survival rates on the Titanic using a table of data.

Type: Problem-Solving Task

Parent Resources

Vetted resources caregivers can use to help students learn the concepts and skills in this benchmark.

Problem-Solving Tasks

Rain and Lightning:

This problem solving task challenges students to determine if two weather events are independent, and use that conclusion to find the probability of having similar weather events under certain conditions.

Type: Problem-Solving Task

Alex, Mel, and Chelsea Play a Game:

This task combines the concept of independent events with computational tools for counting combinations, requiring fluent understanding of probability in a series of independent events.

Type: Problem-Solving Task

Breakfast Before School:

The purpose of this task is to assess a student's ability to explain the meaning of independence in a simple context.

Type: Problem-Solving Task

The Titanic 2:

This task lets students explore the concepts of probability as a fraction of outcomes using two-way tables.

Type: Problem-Solving Task

The Titanic 3:

This problem solving task asks students to determine probabilities and draw conclusions about the survival rates on the Titanic using a table of data.

Type: Problem-Solving Task