In a class of 18 students, 8 have a cat and 7 have a dog. There are 3 students who have a cat and a dog. What is the probability that a student has a cat given that they do not have a dog?Answer:
Q. In a class of 18 students, 8 have a cat and 7 have a dog. There are 3 students who have a cat and a dog. What is the probability that a student has a cat given that they do not have a dog?Answer:
Determine Number of Students: First, we need to determine the number of students who have only a cat and not a dog. We know that 8 students have a cat and 3 of those also have a dog. So, the number of students who have only a cat is the total number of students with a cat minus the number of students who have both a cat and a dog.Calculation: 8 (students with a cat) - 3 (students with both a cat and a dog) = 5 (students with only a cat).
Find Total Students Without Dog: Next, we need to find out the total number of students who do not have a dog. Since 7 students have a dog and 3 of those also have a cat, we subtract the number of students with a dog from the total number of students to get the number of students without a dog.Calculation: 18 (total students) −7 (students with a dog) =11 (students without a dog).
Calculate Probability Given No Dog: Now, we can calculate the probability that a student has a cat given that they do not have a dog. This is the number of students with only a cat divided by the number of students without a dog.Calculation: Probability = 11 (students without a dog)5 (students with only a cat).
Calculate Probability: The probability is therefore 115.
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