In a class of 30 students, 10 have a cat and 21 have a dog. There are 2 students who do not have a cat or 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 30 students, 10 have a cat and 21 have a dog. There are 2 students who do not have a cat or 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 do not have a dog. Since there are 2 students who do not have a cat or a dog, we subtract this number from the total number of students to find the number of students who have a dog or a cat but not a dog.Total number of students = 30Number of students with a dog = 21Number of students with neither a cat nor a dog = 2Number of students without a dog = Total number of students - Number of students with a dogNumber of students without a dog = 30−21Number of students without a dog = 9
Find Students with Only a Cat: Next, we need to find out how many of those students without a dog have a cat. Since there are 10 students with a cat and 2 students with neither a cat nor a dog, we subtract the number of students with neither from the total number of students with a cat to get the number of students with only a cat.Number of students with a cat =10Number of students with neither a cat nor a dog =2Number of students with only a cat = Number of students with a cat − Number of students with neither a cat nor a dogNumber of students with only a cat =10−2Number of students with only a cat =8
Calculate Probability: 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.Probability = Number of students without a dogNumber of students with only a catProbability = 98
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