Lemma
MediumDiscrete distributions
OpenStax, Introductory Statistics 2e §4.2 Mean or Expected Value and Standard Deviation · Exercise 15 · Probability · Discrete distributions

Mean or Expected Value and Standard Deviation · Exercise 15

A ballet instructor is interested in knowing what percent of each year's class will continue on to the next, so that she can plan what classes to offer. Over the years, she has established the following probability distribution.

On average, how many years would you expect a child to study ballet with this teacher?

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OpenStax, Introductory Statistics 2e · §4.2 Mean or Expected Value and Standard Deviation · Exercise 15

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