Question 8

You are given 50 white marbles, 50 black marbles and two jars. You need to put 100 marbles in any of these two jars. The jars will then be shaken and you will be asked to pick one marbles from either jar. How would you distribute the marbles in two are to maximize the possibility of picking a white marble blind folded?

Solution

The probability of picking the white is 0.5*(Probability of white in Jar1) + 0.5*(Probability of white in Jar2)

To maximize the probability we can put 1 white marble in jar 1. Hence the probability of white in jar 1 = 1

The remaining 49 white and 50 black can be put in Jar 2. Thus, the Probability of white in Jar 2 = 49/99.

All other options give less probability

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