Table of contents
- 0. Review of Algebra4h 16m
- 1. Equations & Inequalities3h 18m
- 2. Graphs of Equations43m
- 3. Functions2h 17m
- 4. Polynomial Functions1h 44m
- 5. Rational Functions1h 23m
- 6. Exponential & Logarithmic Functions2h 28m
- 7. Systems of Equations & Matrices4h 6m
- 8. Conic Sections2h 23m
- 9. Sequences, Series, & Induction1h 19m
- 10. Combinatorics & Probability1h 45m
10. Combinatorics & Probability
Probability
Problem 51
Textbook Question
In Exercises 49–52, a single die is rolled twice. Find the probability of rolling an even number the first time and a number greater than 2 the second time.
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Step 1: Identify the sample space for a single die roll, which is {1, 2, 3, 4, 5, 6}.
Step 2: Determine the probability of rolling an even number on the first roll. The even numbers on a die are {2, 4, 6}.
Step 3: Calculate the probability of rolling an even number on the first roll, which is the number of favorable outcomes (3) divided by the total number of outcomes (6).
Step 4: Determine the probability of rolling a number greater than 2 on the second roll. The numbers greater than 2 are {3, 4, 5, 6}.
Step 5: Calculate the probability of rolling a number greater than 2 on the second roll, which is the number of favorable outcomes (4) divided by the total number of outcomes (6). Multiply the probabilities from Step 3 and Step 5 to find the combined probability.
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Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Probability Basics
Probability is a measure of the likelihood of an event occurring, expressed as a number between 0 and 1. In this context, it involves calculating the chances of specific outcomes when rolling a die. Understanding how to determine the total number of possible outcomes is crucial for calculating probabilities.
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Independent Events
In probability, independent events are those whose outcomes do not affect each other. When rolling a die twice, the result of the first roll does not influence the second roll. This concept is essential for calculating the combined probability of multiple events occurring in sequence.
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Event Outcomes
Identifying the specific outcomes of interest is key to solving probability problems. In this case, the first event is rolling an even number (2, 4, or 6), and the second event is rolling a number greater than 2 (3, 4, 5, or 6). Understanding how to count these favorable outcomes relative to the total possible outcomes is necessary for accurate probability calculation.
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Complementary Events
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