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Solve the following problem : Identify the random variable as discrete or continuous in each of the following. Identify its range if it is discrete. Twelve of 20 white rats available for an experimen - Mathematics and Statistics

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Solve the following problem :

Identify the random variable as discrete or continuous in each of the following. Identify its range if it is discrete.

Twelve of 20 white rats available for an experiment are male. A scientist randomly selects 5 rats and counts the number of female rats among them.

Sum

Solution

There are 12 male rats and 8 female rats, i.e., finite number of female rats.
∴ X is a discrete r.v.
Range of X = {0, 1, 2, 3, 4, 5}.

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Types of Random Variables
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Chapter 8: Probability Distributions - Part I [Page 155]

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