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A bag contains 8 red balls and 12 blue balls. One ball Is drawn at random and replaced with 5 green balls. A second ball was drawn without replacement. What Is the probability that first ball drawn is red In colour and the second ball drawn Is blue in colour?

A bag contains 8 red balls and 12 blue balls. One ball Is drawn at random and replaced with 5 green balls. A second ball was drawn without replacement. What Is the probability that first ball drawn is red In colour and the second ball drawn Is blue in colour? Correct Answer 1/5

Calculation:

⇒ The total number of red and blue ball = 8 + 12 = 20

⇒ The total number of after 5 balls replacement = 20 - 1 + 5 = 24

⇒ Probability to first ball is res colour = 8/20

⇒ Probabaility of second ball is blue colour = 12/24

⇒ The required probability = (8/20) × (12/24) = 1/5

∴ The required result will be 1/5.

Additional Information

The probability = (The required events)/(Total events)

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