Check sibling questions


Transcript

Example 2 A family has two children. What is the probability that both the children are boys given that at least one of them is a boy ? A Family has two children Let girls be denoted by ‘g’ & boys be denoted by ‘b’ S = {(g, g), (g, b), (b, g), (b, b)} We need to find the probability that both the children are boys, given at least one them is a boys E: Both the children are boys F: At least one of the children is a boys We need to find P(E|F) E : both the children are boys E = {(b, b)} P(E) = 𝟏/𝟒 F : at least one of the children is a boy F = {(g, b), (b, g), (b, b)} P(F) = 𝟑/𝟒 Also, E ∩ F = {(b, b)} P(E ∩ F ) = 𝟏/𝟒 Now, P(E|F) = (𝑃(𝐸 ∩ 𝐹))/(𝑃(𝐹)) = (1/4)/(3/4) = 𝟏/𝟑

  1. Chapter 13 Class 12 Probability
  2. Serial order wise

About the Author

Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 14 years. He provides courses for Maths, Science and Computer Science at Teachoo