Nonsense answers well be reported LEARNING ACTIVITIES:

Learning Activity 1

Defective Cell Phones

Recall that a variable is a characteristic or attribute that can assume different values. We use capital letters to denote or represent a variable. In this lesson, we shall discuss variables that are associated with probabilities, called random variables.



Suppose three cell phones are tested at random. We want to find out the number of defective cell phones that occur. Thus, to each outcome in the sample space we shall assign a value. These are 0, 1, 2, or 3. If there is no defective cell phone, we assign the number 0; if there is 1 defective cell phone, we assign the number 1; if there are 2 defective cell phones, we assign the number 2; and 3, if there are 3 defective cell phones. The number of defective cell phones is a random variable. The possible values of this random variable are 0, 1, 2, and 3.

Illustration:

Let D represent the defective cell phone and N represent the non-defective cell phone. If we let X be the random variable representing the number of defective cell phones, can you show the values of the random variable X? Complete the table below to show the values of the random variable.

​