Amitabh Shrivastava
Last Activity: 13 Years ago
The answer is simple take the worst possible case. the man piks up all the balls which do not have 15 of same colour so the man piks up 12 yellow,10 orange,10 blue balls now to further delay the man piks up one green then one red then one brown until he has 15 of green balls ie he piks up 15 green 14 red and 14 brown balls. thus the total no of trials is 12+10+10+14+14+15=75 trials
I understand that this a bit confusing so feel free to contact for any queries.
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