Suppose that participants with distinct names arrive for a conference. The organizers have prepared name-tags for all of them, but by mistake allocate the name-tags randomly to the participants. What is the expected number of participants who will receive their own name-tag?
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Suppose that n participants with distinct names arrive for a conference. The organizers have prepared name-tags for all of them, but by mistake allocate the name-tags randomly to the participants. What is the expected number of participants who will receive their own name-tag? (A) n/2 (B) n/(n-2) (C) 1 (D) (n-1)/n
Probability and Bayes' theorem has come up 190 times in 7 exams since 2004.
This question is on Expectation by indicator variables, part of Probability and Bayes' theorem in Statistics.
Finding expected counts by adding up simple 0-1 variables.
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Question from the DSE 2021 paper. Solutions are TestStop's own. Not affiliated with or endorsed by any examination authority.