NCERT Example 22 - Probability
Question: Coloured balls are distributed in four boxes as shown in the table (Box I: 3 black, 4 white, 5 red, 6 blue; II: 2 of each colour; III: 1 black, 2 white, 3 red, 1 blue; IV: 4 black, 3 white, 1 red, 5 blue). A box is selected at random and a ball drawn is black. Find the probability that it came from Box III.
Answer: P(Box III | black) = 156/947.
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