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Algebra

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29 Dec 2007 10:21:50 IST

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Probablity ques 2

None

Three critics review a book .Odds in favour of the book are 5:2,4:3,3:4 respectively for the three critics.Find the probablity that majourity are in favour of the book.

Answer-209/243.

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Jatin Sharma

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29 Dec 2007 11:12:36 IST

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When the odds are given you can find the probability of each liking the book.

Let the probability of the 3 critics liking the buk b A,B,C.

And let A* be the Prob. of them disliking the buk.

Now the probability of the buk being liked by a majority will be:

ABC + ABC* + AB*C + A*BC.

And that is your answer.....

harsh _27

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29 Dec 2007 11:16:47 IST

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let the persons be a,b,c

probability that a is in favour = P[a] =5/7

P[a^]=2/7 ...........similarly so on

P(majority are in favour) = P[any 2 in f] + P[3 are in f]

                                     = P[a]P[b]P[c^] +P[a]P[b^]P[c] +P[a^]P[b]P[c] +P[a]P[b]P[c]

                                     =5/7x4/7x4/7 + 5/7x3/7x3/7+2/7x4/7x3/7 + 5/7x4/7x2/7

                                     = 80+45+24+60/343

                                     = 209/343

harsh _27

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29 Dec 2007 11:28:29 IST

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plz check ur nudge book...

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