Question
There are 5 wrong questions in a question paper, consisting of 10 questions. If 6 questions are selected from this question paper, then the probability that there will be exactly 3 wrong questions among them is
Answers
mathhelper
prob of wrong = 5/10 = 1/2
Prob(exactly 3 wrong when selecting 6)
= (6,3)(1/2)^3 (1/2)^3
= 20(1/64) = 5/16
Prob(exactly 3 wrong when selecting 6)
= (6,3)(1/2)^3 (1/2)^3
= 20(1/64) = 5/16