High School

Select the correct answer.

A restaurant has a total of 60 tables. Of those tables, 38 are round, and 13 are located by the window. There are 6 round tables by the window.

If tables are randomly assigned to customers, what is the probability that a customer will be seated at a round table or by the window?

A. [tex]$\frac{29}{60}$[/tex]
B. [tex]$\frac{45}{60}$[/tex]
C. [tex]$\frac{41}{60}$[/tex]
D. [tex]$\frac{47}{60}$[/tex]

Answer :

We start by noting that there are a total of [tex]$60$[/tex] tables, of which [tex]$38$[/tex] are round and [tex]$13$[/tex] are by the window. However, since [tex]$6$[/tex] tables are both round and by the window, we must be careful not to count those twice.

Using the principle of inclusion-exclusion, the number of tables that are either round or by the window is calculated by

[tex]$$
|\,\text{Round} \cup \text{Window}| = |\,\text{Round}| + |\text{Window}| - |\,\text{Round} \cap \text{Window}|.
$$[/tex]

Substitute the given values:

[tex]$$
|\,\text{Round} \cup \text{Window}| = 38 + 13 - 6 = 45.
$$[/tex]

Next, the probability that a randomly assigned table is either round or by the window is the number of favorable outcomes divided by the total number of tables:

[tex]$$
\text{Probability} = \frac{45}{60}.
$$[/tex]

Thus, the correct answer is

[tex]$$
\frac{45}{60}.
$$[/tex]>

So, the answer is [tex]$\boxed{\frac{45}{60}}$[/tex], which corresponds to option B.