You are an editor of a magazine and every day you get two letters from correspondents, each as likely to be from a male as a female. The postman delivers one letter at a time and follows a 'ladies first' policy (he delivers a female's letter first if there is one). You have already received the first letter for today and it is from a female correspondent. What is the probability that the second letter will also be from a female?
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You are an editor of a magazine and every day you get two letters from correspondents, each as likely to be from a male as a female. The postman delivers one letter at a time and follows a 'ladies first' policy (he delivers a female's letter first if there is one). You have already received the first letter for today and it is from a female correspondent. What is the probability that the second letter will also be from a female? (A) 1/2 (B) 1/4 (C) 1/3 (D) 2/3
Probability and Bayes' theorem has come up 190 times in 7 exams since 2004.
This question is on Conditional probability and the multiplication rule, part of Probability and Bayes' theorem in Statistics.
Probabilities that change when you know something has happened.
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Question from the DSE 2013 paper. Solutions are TestStop's own. Not affiliated with or endorsed by any examination authority.