Answer :
To find the probability that a customer will be seated at a round table or by the window, we can use the formula for the probability of either-or events:
[tex]\[ \text{P(A or B)} = \text{P(A)} + \text{P(B)} - \text{P(A and B)} \][/tex]
where:
- P(A) is the probability of a table being round.
- P(B) is the probability of a table being by the window.
- P(A and B) is the probability of a table being both round and by the window.
Let's find each probability:
1. Total Number of Tables: 60
2. Number of Round Tables (P(A)): 38 out of 60 tables are round.
3. Number of Tables by the Window (P(B)): 13 out of 60 tables are by the window.
4. Number of Round Tables by the Window (P(A and B)): 6 tables are both round and by the window.
Now, plug these values into the formula:
[tex]\[ \text{P(round or window)} = \frac{38}{60} + \frac{13}{60} - \frac{6}{60} \][/tex]
[tex]\[ = \frac{38 + 13 - 6}{60} \][/tex]
[tex]\[ = \frac{45}{60} \][/tex]
So, 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 0.75. Therefore, the correct answer is:
D. [tex]\(\frac{45}{60}\)[/tex]
[tex]\[ \text{P(A or B)} = \text{P(A)} + \text{P(B)} - \text{P(A and B)} \][/tex]
where:
- P(A) is the probability of a table being round.
- P(B) is the probability of a table being by the window.
- P(A and B) is the probability of a table being both round and by the window.
Let's find each probability:
1. Total Number of Tables: 60
2. Number of Round Tables (P(A)): 38 out of 60 tables are round.
3. Number of Tables by the Window (P(B)): 13 out of 60 tables are by the window.
4. Number of Round Tables by the Window (P(A and B)): 6 tables are both round and by the window.
Now, plug these values into the formula:
[tex]\[ \text{P(round or window)} = \frac{38}{60} + \frac{13}{60} - \frac{6}{60} \][/tex]
[tex]\[ = \frac{38 + 13 - 6}{60} \][/tex]
[tex]\[ = \frac{45}{60} \][/tex]
So, 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 0.75. Therefore, the correct answer is:
D. [tex]\(\frac{45}{60}\)[/tex]