In a certain Algebra 2 class of 23 students, 15 of them play basketball and 16 of them play baseball. There are 3 students who play neither sport. What is the probability that a student chosen randomly from the class plays both basketball and baseball?
Q. In a certain Algebra 2 class of 23 students, 15 of them play basketball and 16 of them play baseball. There are 3 students who play neither sport. What is the probability that a student chosen randomly from the class plays both basketball and baseball?
Calculate total students: Calculate the total number of students who play at least one sport. Since 3 students play neither sport, the number of students playing at least one sport is 23−3=20.
Use inclusion-exclusion principle: Use the principle of inclusion-exclusion to find the number of students who play both sports. Let A be the set of students who play basketball and B be the set of students who play baseball. According to the principle, ∣A∪B∣=∣A∣+∣B∣−∣A∩B∣. We know ∣A∪B∣=20 (from step 1), ∣A∣=15, and ∣B∣=16. Plugging in these values, we get 20=15+16−∣A∩B∣. Solving for ∣A∩B∣, we find ∣A∩B∣=15+16−20=11.
Calculate probability: Calculate the probability that a randomly chosen student plays both sports. The probability is the number of students who play both sports divided by the total number of students. Probability = Total students∣A∩B∣=2311.
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