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There are 20 girls and 60 boys in a class. Half of the girls and half of the boys are first class students. A student ¡s selected at random. What is the probability that the student ¡s either a boy or a first class holder. Select the correct answer from above options

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n(S) = 20 + 60 = 80 Let A: student is a boy n(A) 60 P(A) = 60 80 60 = 3 4 3 Let B: student is a class holder 1 class = 30 boys + lo girls = 40 P(B) = 40 80 40 = 1 2 1 Let (A ∩ B) = n(Student is a boy and I class holder) = 30 P(A) = (A ∩ B) = 30 80 30 = 3 8 3 ∴ P(Student is a boy of first class holder)

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