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# Random variables

AP Stats: UNC (BI), UNC‑3 (EU), VAR (BI), VAR‑5 (EU)

AP Stats: VAR (BI), VAR‑5 (EU), VAR‑5.A (LO), VAR‑5.A.1 (EK), VAR‑5.A.2 (EK), VAR‑5.A.3 (EK), VAR‑5.C (LO), VAR‑5.C.1 (EK), VAR‑5.C.2 (EK), VAR‑5.C.3 (EK), VAR‑5.D (LO), VAR‑5.D.1 (EK)

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Probability with discrete random variablesGet 3 of 4 questions to level up!

Mean (expected value) of a discrete random variableGet 3 of 4 questions to level up!

Standard deviation of a discrete random variableGet 3 of 4 questions to level up!

AP Stats: VAR (BI), VAR‑6 (EU), VAR‑6.A (LO), VAR‑6.A.2 (EK), VAR‑6.A.3 (EK), VAR‑6.B (LO), VAR‑6.B.1 (EK), VAR‑6.B.2 (EK)

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Probability in density curvesGet 3 of 4 questions to level up!

Probability in normal density curvesGet 3 of 4 questions to level up!

AP Stats: VAR (BI), VAR‑5 (EU), VAR‑5.F (LO), VAR‑5.F.1 (EK)

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Transforming random variablesGet 3 of 4 questions to level up!

AP Stats: VAR (BI), VAR‑5 (EU), VAR‑5.E (LO), VAR‑5.E.1 (EK), VAR‑5.E.2 (EK), VAR‑5.E.3 (EK)

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Combining random variablesGet 3 of 4 questions to level up!

Combining normal random variablesGet 3 of 4 questions to level up!

AP Stats: UNC (BI), UNC‑3 (EU), UNC‑3.A (LO), UNC‑3.A.2 (EK), UNC‑3.B (LO), UNC‑3.B.1 (EK)

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Identifying binomial variablesGet 3 of 4 questions to level up!

Binomial probability formulaGet 3 of 4 questions to level up!

Calculating binomial probabilityGet 3 of 4 questions to level up!

AP Stats: UNC (BI), UNC‑3 (EU), UNC‑3.A (LO), UNC‑3.A.2 (EK), UNC‑3.B (LO), UNC‑3.B.1 (EK), UNC‑3.C (LO), UNC‑3.C.1 (EK)

AP Stats: UNC (BI), UNC‑3 (EU), UNC‑3.E (LO), UNC‑3.E.1 (EK), UNC‑3.E.2 (EK), UNC‑3.F (LO), UNC‑3.F.1 (EK)

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Binomial vs. geometric random variablesGet 3 of 4 questions to level up!

Geometric probabilityGet 3 of 4 questions to level up!

Cumulative geometric probabilityGet 3 of 4 questions to level up!

### About this unit

A random variable is some outcome from a chance process, like how many heads will occur in a series of 20 flips (a discrete random variable), or how many seconds it took someone to read this sentence (a continuous random variable). We calculate probabilities of random variables, calculate expected value, and look what happens when we transform and combine random variables.AP® is a registered trademark of the College Board, which has not reviewed this resource.