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प्रश्न
A bag contains 5 red, 8 white and 7 black balls. A ball is drawn at random from the bag. Find the probability that the drawn ball is neither white nor black.
उत्तर
Total no. of possible outcomes = 20 {5 red, 8 white & 7 black}
Let E ⟶ be event of getting neither white nor black ball
No. of favourable outcomes = 20 – 8 – 7 = 5 {total balls – no. of white balls – no. Of black balls}
Probability, P(E) =`"No.of favorable outcomes"/"Total no.of possible outcomes"`
P(E) = 5/20 =1/4
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