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Refer to Question 41 above. If a white ball is selected, what is the probability that it came from Bag 2

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Question

Refer to Question 41 above. If a white ball is selected, what is the probability that it came from Bag 2

Sum
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Solution

We will use here Bayes’ Theorem

`"P"("E"_2/"F") = ("P"("E"_2)*"P"("F"/"E"_2))/("P"("E"_1) * "P"("F"/"E"_1) + "P"("E"_2) * "P"("F"/"E"_2) + "P"("E"_3) * "p"("F"/"E"_3))`

= `(2/6*1/3)/(1/6*0 + 2/6*1/3 + 3/6*1)`

= `(2/18)/(2/18 + 3/6)`

= `2/11`

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Chapter 13: Probability - Exercise [Page 276]

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NCERT Exemplar Mathematics Exemplar [English] Class 12
Chapter 13 Probability
Exercise | Q 42.(i) | Page 276

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