College

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

Answer :

To solve the problem of finding the probability that a customer will be seated at a round table or by the window, we can follow these steps:

1. Identify the Total Number of Tables:
- The restaurant has a total of 60 tables.

2. Identify the Number of Round Tables and Tables by the Window:
- There are 38 round tables.
- There are 13 tables by the window.

3. Identify the Intersection:
- There are 6 tables that are both round and by the window.

4. Apply the Inclusion-Exclusion Principle:
- We want to find the probability of a table being round or by the window. We use the formula for the probability of the union of two events:
[tex]\[
P(\text{Round or Window}) = P(\text{Round}) + P(\text{Window}) - P(\text{Round and Window})
\][/tex]
- Substituting the corresponding numbers:
- [tex]\( P(\text{Round}) = 38 \)[/tex]
- [tex]\( P(\text{Window}) = 13 \)[/tex]
- [tex]\( P(\text{Round and Window}) = 6 \)[/tex]

5. Calculate the Number of Favorable Outcomes:
- The number of tables that are either round or by the window is:
[tex]\[
38 + 13 - 6 = 45
\][/tex]

6. Calculate the Probability:
- The probability is the number of favorable outcomes divided by the total number of tables, which is:
[tex]\[
\frac{45}{60}
\][/tex]

Therefore, the probability that a customer will be seated at a round table or by the window is [tex]\(\frac{45}{60}\)[/tex], which simplifies to [tex]\(\frac{3}{4}\)[/tex] or 0.75.

Thus, the correct answer is choice D: [tex]\(\frac{45}{60}\)[/tex].