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Discrete Random Variables De nition (Discrete Random Variable) A discrete random variable is a variable which can only take-on a countable number of values ( nite or countably in nite) Example (Discrete Random Variable) Flipping a coin twice, the random variable Number of Heads 2f0;1;2gis a discrete random variable. and a and b are fixed numbers, then. The probability that X is between
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Let X represent the sum of two dice. /BBox [0 0 5669.291 8] << In this way, the discrete quantitative variables are those that only take into account numbers within a scale of values that can be separated from each other, indicating specific values (StatTrek.com, 2017). There are also simpler cases of statistics that involve discrete variables for study.

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