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Suppose that 7 green balls and 9 purple balls are placed in an urn. Two balls are then drawn in succession. What is the probability that the second ball drawn is a purple ball if the first ball is replaced before the second is drawn?

1 Answer

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Answer: 0.2461

Explanation:

There are 16 balls in total, and 9 of them are purple. If the first ball drawn is replaced before the second is drawn, then the number of purple balls and the number of total balls in the urn remain the same for the second draw.

The probability of drawing a purple ball on the first draw is 9/16. Since the ball is replaced, the probability of drawing a purple ball on the second draw is also 9/16.

The probability that the second ball drawn is a purple ball, given that the first ball drawn was replaced and was a green ball:

(7/16) * (9/16) = 63/256 ≈ 0.2461

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