Calculating Expected Value
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Objective
I can calculate the expected value of a random variable.
Part 1 of 4
Warm-up video
Khan Academy · 4:32Vetted channel
We don't generate video — this one is by Khan Academy on YouTube. The practice questions and exit ticket below were drafted by AI for this objective, and every question is editable in the teacher guide.
Part 2 of 4
Key concepts
3 concepts
- 1
A discrete random variable has a finite number of values, and a valid probability distribution has a combined probability of one.
- 2
The expected value of a discrete random variable is the weighted sum of the various outcomes, weighted by their probabilities.
- 3
The expected value, or mean, of a random variable can be a non-integer value even if the random variable only takes on integer values.
Part 3 of 4
Practice
12 questions
What is the expected value of a discrete random variable also known as?
Explain in your own words what the expected value of a discrete random variable represents.
Part 4 of 4
Exit ticket
Quick comprehension check
“A discrete random variable Y represents the number of days per week a person exercises. The probability distribution is as follows: P(Y=0) = 0.2, P(Y=1) = 0.1, P(Y=2) = 0.3, P(Y=3) = 0.4. What is the expected value of Y? Show your work.”
Sample answer included in the free materials
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