The owner of a local movie theater keeps track of the number of tickets sold in each purchase and makes a probability distribution based on these records. Let [tex]$X$[/tex] represent the number of tickets bought in one purchase. The distribution for [tex]$X$[/tex] is given in the table.

\begin{tabular}{|c|c|c|c|c|c|}
\hline
\begin{tabular}{c}
Number of \\
Tickets
\end{tabular}
& 1
& 2
& 3
& 4
& 5 \\
\hline
Probability
& 0.29
& 0.44
& 0.19
& 0.06
& 0.02 \\
\hline
\end{tabular}

Which is the correct interpretation of the standard deviation?

A. The number of tickets purchased typically varies from the expected value by 0.95 tickets.

B. If many, many purchases are made, the expected number of tickets purchased is 2.1.

C. The mean number of tickets purchased typically varies from the expected value by 0.95 tickets.

D. The mean number of tickets purchased typically varies from the expected value by 0.89 tickets.



Answer :

To solve this problem, we need to understand the standard deviation and its relation to the expected value (mean) of a probability distribution.

1. Expected Value ([tex]$\mu$[/tex]):
- The expected value, also known as the mean, of a random variable [tex]$X$[/tex] represents the long-run average number of tickets purchased in each transaction.

2. Variance ([tex]$\sigma^2$[/tex]):
- The variance measures the spread of the number of tickets purchased around the mean. It is calculated as the average of the squared differences from the expected value.

3. Standard Deviation ([tex]$\sigma$[/tex]):
- The standard deviation is the square root of the variance. It provides a measure of the average distance of each ticket count from the expected value.

Given that the expected value of the number of tickets purchased is 2.08, the variance is 0.8936, and the standard deviation is 0.9453041838477179, we interpret these results as follows:

- The expected value of 2.08 indicates that, on average, customers purchase about 2.08 tickets per transaction.

- The variance of 0.8936 suggests the spread or variability in the number of tickets purchased.

- The standard deviation of approximately 0.95 tickets indicates that the number of tickets purchased typically deviates from the mean by around 0.95 tickets. In other words, most ticket purchases vary from the mean (2.08 tickets) by about 0.95 tickets.

Thus, the correct interpretation of the standard deviation among the provided options is:

The number of tickets purchased typically varies from the expected value by 0.95 tickets.

Answer:

The number of tickets purchased typically varies from the expected value by 0.95 tickets.

Step-by-step explanation: