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OpenStax, Introductory Statistics 2e §4.1 Probability Distribution Function (PDF) for a Discrete Random Variable · Exercise 12 · Probability · Discrete distributions

Probability Distribution Function (PDF) for a Discrete Random Variable · Exercise 12

Ellen has music practice three days a week. She practices for all of the three days 85% of the time, two days 8% of the time, one day 4% of the time, and no days 3% of the time. One week is selected at random.

We know that for a probability distribution function to be discrete, it must have two characteristics. One is that the sum of the probabilities is one. What is the other characteristic?

Its source prints no answer for this problem, so there's nothing to check against.

~8 minWritten answer · compare with the solution

OpenStax, Introductory Statistics 2e · §4.1 Probability Distribution Function (PDF) for a Discrete Random Variable · Exercise 12

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