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6.1. Random Variables: Definition
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4 cards from this lesson. Good the night before a test.
Try these first
- 1.
What is a random variable?
Hint
Think about how outcomes in experiments can be quantified.
- 2.
Give an example of a discrete random variable.
Hint
Consider things that can be counted.
- 3.
What are random variables used for?
- To predict outcomes
- To count items
- To measure time
Hint
Think about where uncertainty is present.
- 4.
Is a temperature reading a discrete random variable?
- True
- False
Hint
Consider how temperature can change gradually.
- 5.
In a game, a player wins 1, or $2 with probabilities 0.5, 0.3, and 0.2 respectively. Calculate the expected value of their winnings.
Hint
Use the expectation formula with given probabilities.
- 6.
A continuous random variable has a PDF given by f(x) = 3x² for 0 ≤ x ≤ 1. Find the expectation of this variable.
Hint
Integrate the product of x and the PDF within the defined limits.
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