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7.1.1. Random Variables and Probability Distributions
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Mixed questions from across the chapter. Your answers get marked.
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3 cards from this lesson. Good the night before a test.
Try these first
- 1.
What is a random variable?
Hint
Think of it as a representation of outcomes in numbers.
- 2.
Define a discrete random variable.
Hint
Consider examples like dice rolls or number of students.
- 3.
What is the normalization condition for a PDF?
Hint
Consider how probabilities relate to areas in geometry.
- 4.
True or false: CDF can give the probability of a random variable being greater than a specific value.
- True
- False
Hint
Think about what CDF shows and what it doesn't.
- 5.
A continuous random variable has a PDF defined as f(x) = kx for 0 ≤ x ≤ 2. Find the value of k and then the probability that X < 1.
Hint
Remember to normalize the PDF first, then use integration.
- 6.
The mean of a random variable X is defined by the integral μ = ∫ x f(x) dx. For the PDF f(x) = 2x (0 ≤ x ≤ 1), calculate the mean.
Hint
The integration step is crucial for finding the expected value!
Exercises
Total Questions
2
Estimated Time
4 min
Passing Score
70%
Instructions
- Read each question carefully
- You can use hints if you need help
- Complete all questions before submitting
4 more questions available
Enrol freeQuiz
Total Questions
2
Estimated Time
4 min
Passing Score
70%
Instructions
- Read each question carefully
- You can use hints if you need help
- Complete all questions before submitting
1 more question available
Enrol freeChallenge Problems
Total Questions
2
Estimated Time
4 min
Passing Score
70%
Instructions
- Read each question carefully
- You can use hints if you need help
- Complete all questions before submitting