Respuesta :
A discrete random variable has a countable number of possible values. In this case I am pretty sure it is either none of the above or maybe the phone one.
Discrete random variables are simply countable, which should be a finite number and it should not change continuously. So, Time worked on a job is the discrete random variable among the four options.
Discrete random variable:
A random variable is said to be discrete if an experiment gives a finite number that is countable and should not change continuously.
Here, Time worked on a job has a fixed time for a job has to be done. So, it is a discrete random variable.
Some more examples of Discrete random variables are:
No. of girls in a family,
No. of outcomes of the head when two coins are flipped.
No. of defective street lights out of 100 bulbs in a certain area.
No. of the possible outcome of getting 4 when a dice is thrown twice.
Wrong answers with explanation:
The weight of a child changes as the child grows. So, it cannot be a discrete random variable.
The first digit of a phone number also changes for each and every person, whenever a person changes his /her number automatically will get a new number and it will have a different digit. So, it cannot be a discrete random variable.
The length of fish also varies according to the different sizes of fish. So, it cannot be a discrete random variable.
Know more about the discrete random variables:
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