Question

In Exercises 7–14, determine whether a probability

distribution is given. If a probability distribution is given, find its mean and standarddeviation. If a probability distribution is not given, identify the requirements that are notsatisfied.

In a Microsoft Instant Messaging survey, respondents were asked to choose the most fun way to flirt, and the accompanying table is based on the results.

x	P(x)
E-mail	0.06
In person	0.55
Instant message	0.24
Text message	0.15

Short answer

The requirement that x is a numerical random variable is not satisfied.

Step-by-step solution

Given information

The probability distribution for the most fun way to flirt is provided.

Identify the requirements for a probability distribution

Letthe variable x represent the type of messaging.

The requirements are as follows.

1)The variablex is a numerical random variable,which is not satisfied as the variable cannot be expressed in the number form.

2)The sum of the probabilities is computed as

$$\begin{gathered} \sum P\left(x\right)=0.06+0.55+0.24+0.15 \\ =1 \end{gathered}$$

Therefore, the sum of the probabilities is 1.

3) Each value of P(x) is between 0 and 1.

Thus, the requirement that x is a numerical random variable is not satisfied.

Therefore, the mean and standard deviation cannot be computed.