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A bagcontains 5 white, 7 red and 3 black balls. If three balls are drawn one by onewithout replacement, find the probability that none is red. |
Answer» There are total `15` balls and red balls are `7`. `:.` Probability that first ball is not red `= 8/15`. Now, there are `14` total balls and `7` balls are not red. `:.` Probability of drawing second ball that is not red `= 7/14 = 1/2` Now, there are `13` total balls and `6` balls are not red. `:.` Probability of drawing third ball that is not red `= 6/13` `:.` Required probability `= 8/15**1/2**6/13 = 8/65 ` |
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