Question

pls help me with this .... pls !!




a bag contains 6 red, 5 blue and 7 green balls . a ball is dream at random from the bag . find the probability that the ball drawn is free in colour . ( with formula )

Answer 1

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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