Question
In a class of 30 students, 18 students like mathematics,
15 like science, and 8 like both subjects. What is the probability that a randomly selected student likes at least one of the two subjects?Solution
Let the total number of students be 30. Students who like mathematics = 18 Students who like science = 15 Students who like both mathematics and science = 8 Using the formula for the union of two sets: P(Math or Science) = P(Math) + P(Science) - P(Math and Science) P(Math or Science) = 18 + 15 - 8 = 25 The probability is: P = 25 / 30 = 5 / 6 Correct Option: b
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