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Mathematics Worksheet
🎰 Random Variables
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List the possible values of a random variable.Find P(X = k).Compute the expected value E(X).Distinguish discrete from continuous variables.📚 Quick Recap
A random variable assigns a number to every outcome of a random experiment, turning abstract outcomes into something we can calculate with.
🧠 Section A · Concept Check ● BEGINNER 4 × 1 = 4
1A coin is flipped 3 times; X = number of heads. The possible values are:
2For that experiment, P(X = 2) =:
3For that experiment, P(X = 0) =:
4Using probabilities 1/8, 3/8, 3/8, 1/8 for X=0,1,2,3, E(X) =:
🧮 Section B · Problem Solving ● INTERMEDIATE 2 + 3×3 = 11
5E(X) = Σ x · .
6For 3 coins, the possible values of X (heads) are .
7A coin is flipped 3 times; X = number of heads. List the possible values of X.
8Find P(X = 2) for the experiment above.
9Find P(X = 0) for the experiment above.
🚀 Section C · Challenge ● CHALLENGE 5
10Using 1/8, 3/8, 3/8, 1/8 for X=0,1,2,3, find E(X).
💭 Reflection — the most useful thing I learned:
A ___/4 B ___/11 C ___/5 Total ___/20
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1-A 2-A 3-A 4-A | 5 P(X = x) 6 0, 1, 2, 3 7 = 0, 1, 2, 3 8 = 3/8 9 = 1/8 | 10 = 1.5