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Concept explainers
Fill in the blanks.
- a. A ______ is a quantitative variable whose value depends on chance.
- b. A discrete random variable is a random variable whose possible values _______.
a.
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Identify the quantitative variable whose value depends on chance.
Answer to Problem 1RP
A random variable is a quantitative variable whose value depends on chance.
Explanation of Solution
Justification:
Random variable:
A random variable X is a numerical outcome of a probability experiment. Moreover, there is a numerical value which is determined, by chance, for each outcome in the procedure or experiment. Each random variable has a probability distribution, which specifies the probability whose value lies in any given interval.
A random variable is a numerical outcome of a probability experiment.
b.
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Identify the possible values of a discrete random variable.
Answer to Problem 1RP
A discrete random variable is a random variable whose possible value is finite.
Explanation of Solution
Justification:
Discrete random variable:
A discrete random variable is one which takes on only a countable number of values. That is, it takes values 0,1,2,3…. That is, a discrete random variable takes a collection of values which is finite or countable.
A discrete random variable takes a collection of values which is finite or countable.
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