# Ex 13.4, 12 - Chapter 13 Class 12 Probability (Term 2)

Last updated at Feb. 15, 2020 by Teachoo

Last updated at Feb. 15, 2020 by Teachoo

Transcript

Ex 13.4, 12 Two numbers are selected at random (without replacement) from the first six positive integers. Let X denote the larger of the two numbers obtained. Find E(X).The first 6 positive integers are : 1, 2, 3, 4, 5, 6 And they are selected without replacement Let X : be the larger number of two numbers selected The possible outcomes are Sample space = S = {█(█((1, 2),(1, 3),(1, 4),(1, 5),(1, 6),@(2, 1),(2, 3),(2, 4),(2, 5),(2, 6),)@█((3, 1),(3, 2),(3, 4),(3, 5),(3, 6),@(4, 1),(4, 2),(4, 3),(4, 5),(4, 6),)@█((5, 1),(5, 2),(5, 3),(5, 4),(5, 6),@(6, 1),(6, 2),(6, 3),(6, 4),(6, 5) ))} Total number of possible outcomes = 30 The larger number can be : 2, 3, 4, 5 or 6 So, the values of X can be : 2, 3, 4, 5 or 6 Thus, the probability distribution is The mean Expected value is given by 𝝁=𝑬(𝑿)=∑_(𝑖=1)^𝑛▒𝑥𝑖𝑃𝑖 = 2 × 2/30+"3 × " 4/30+ 4 × 6/30+ 5 × 8/30+ 6 × 10/30 = (4 + 12 + 24 + 40 + 60)/30 = 140/30 = 𝟏𝟒/𝟑

Ex 13.4

Ex 13.4, 1

Ex 13.4, 2

Ex 13.4, 3 Important

Ex 13.4, 4 (i)

Ex 13.4, 4 (ii)

Ex 13.4, 4 (iii) Important

Ex 13.4, 5 (i) Important

Ex 13.4, 5 (ii)

Ex 13.4, 6 Important

Ex 13.4, 7 Important

Ex 13.4, 8

Ex 13.4, 9

Ex 13.4, 10 Deleted for CBSE Board 2022 Exams

Ex 13.4, 11 Important Deleted for CBSE Board 2022 Exams

Ex 13.4, 12 Important Deleted for CBSE Board 2022 Exams You are here

Ex 13.4, 13 Important Deleted for CBSE Board 2022 Exams

Ex 13.4, 14 Deleted for CBSE Board 2022 Exams

Ex 13.4, 15 Deleted for CBSE Board 2022 Exams

Ex 13.4, 16 (MCQ) Deleted for CBSE Board 2022 Exams

Ex 13.4, 17 (MCQ) Important Deleted for CBSE Board 2022 Exams

Chapter 13 Class 12 Probability (Term 2)

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Davneet Singh

Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 10 years. He provides courses for Maths and Science at Teachoo.