Four testers independently rank three chocolates (best , then , ); ranks are summed per chocolate across testers. If each tester ranks at random, the probability that chocolate receives a total score of is
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2 marks, −0.666666666666667StatisticsProbability and Bayes' theoremRepeated trials: binomial and geometric probabilitiesModerateabout 3 min
DSE 2015 Question 48: Probability and Bayes' theorem
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Four testers independently rank three chocolates A,B,C (best =1, then 2, 3); ranks are summed per chocolate across testers. If each tester ranks at random, the probability that chocolate A receives a total score of 4 is (A) 1/4 (B) 1/3 (C) 1/27 (D) 1/81
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What this question tests
This question is on Repeated trials: binomial and geometric probabilities, part of Probability and Bayes' theorem in Statistics.
Probabilities from independent repeated experiments.
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