Probability Of Combined Events
Overview
Most interesting probability questions involve more than one thing happening: two dice rolled together, two coins tossed, a counter drawn then another. To handle these combined events we need organised ways of listing every possibility, and two simple rules for combining probabilities. Get organised and even busy-looking questions become straightforward.
In this lesson you will list outcomes with sample space tables, picture overlapping events, and follow the branches of a tree to combine probabilities. The two rules at the heart of it are short and memorable: multiply along the branches for AND, add the separate cases for OR. With these tools you can find the chance of almost any combined event.
Objectives
- Calculate the probability of combined events using, where appropriate: sample space diagrams Venn diagrams tree diagrams.
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Mind map
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Flashcards
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Lesson Note
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Lesson Evaluation
Congratulations on completing the lesson on Probability Of Combined Events. Now that youve explored the key concepts and ideas, its time to put your knowledge to the test. This section offers a variety of practice questions designed to reinforce your understanding and help you gauge your grasp of the material.
You will encounter a mix of question types, including multiple-choice questions, short answer questions, and essay questions. Each question is thoughtfully crafted to assess different aspects of your knowledge and critical thinking skills.
Use this evaluation section as an opportunity to reinforce your understanding of the topic and to identify any areas where you may need additional study. Don't be discouraged by any challenges you encounter; instead, view them as opportunities for growth and improvement.
- Two fair dice are rolled. What is the probability that the scores add up to 7? A. 1/12 B. 1/9 C. 1/6 D. 1/3 Answer: C
- Two fair coins are tossed. What is the probability of getting two heads? A. 1/8 B. 1/4 C. 1/2 D. 3/4 Answer: B
- A fair die is rolled. What is the probability of rolling a 2 or a 5? A. 1/6 B. 1/4 C. 1/3 D. 1/2 Answer: C
- Events A and B are independent with P(A) = 0.5 and P(B) = 0.4. What is P(A and B)? A. 0.1 B. 0.2 C. 0.5 D. 0.9 Answer: B
- Two fair dice are rolled. How many outcomes are in the sample space? A. 6 B. 12 C. 18 D. 36 Answer: D
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