In a class of 29 students, 10 have a cat and 12 have a dog. There are 9 students who do not have a cat or a dog. What is the probability that a student who has a dog also has a cat?Answer:
Q. In a class of 29 students, 10 have a cat and 12 have a dog. There are 9 students who do not have a cat or a dog. What is the probability that a student who has a dog also has a cat?Answer:
Determine Students with Both: Determine the number of students who have both a cat and a dog.We are given:- Total students = 29- Students with a cat = 10- Students with a dog = 12- Students without a cat or dog = 9To find the number of students who have both a cat and a dog, we can use the principle of inclusion-exclusion. The formula is:Number of students with both = (Students with a cat) + (Students with a dog) - (Total students) + (Students without either)Let's calculate this:Number of students with both = 10+12−29+9
Calculate Both Students: Calculate the number of students who have both a cat and a dog.Number of students with both =10+12−29+9Number of students with both =22−29+9Number of students with both =−7+9Number of students with both =2
Calculate Probability: Calculate the probability that a student who has a dog also has a cat.We now know that 2 students have both a cat and a dog. To find the probability that a student who has a dog also has a cat, we divide the number of students who have both by the total number of students who have a dog.The probability is given by:P(Has cat∣Has dog)=Number of students with a dogNumber of students with bothLet's calculate this:P(Has cat∣Has dog)=122
Simplify Probability: Simplify the probability.P(Has cat∣Has dog)=122P(Has cat∣Has dog)=61