Question

A bag contains 6 red, 5 green and 4 yellow coloured balls. 2 balls are drawn at random after one another without replacement then what is the probability that atleat one ball is green?

Answer 1

$\textbf {Hey there, here is the solution.}$

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Total number of balls = 6 + 5 + 4 = 15

Total number of green balls = 5

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P(at least one green) = P(green, then not green) + P(not green, then green) + P(green and green)

P(at least one green) = (5/15)(10/14) + (10/15)(5/14) + (5/15)(4/14)

P(at least one green) = 5/21 + 5/21 + 2/21

P(at least one green) = 12/21

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Answer: The probability is 12/21

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$\textbf {Cheers}$