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Red and Blue Marbles Puzzle
There are 2 identical empty jars alongside the jars there were 50 red & 50 blue marbles kept. You need to put all the marbles into both of the jars in such a way that when any jar is selected at random the probability of picking up a red marble is the highest.
Explanation :
No Best Answer on this question yet!Asked In : Infosys
Put one red marble in 1 jar and the rest all the other marbles in another jar.
So probability of getting
P( red marble ) = P( Jar 1 ) * P( red marble in Jar 1 ) + P( Jar 2 ) * P( red marble in Jar 2 )
P( red marble ) = 0.5 * 1 + 0.5 * 49/99
P( red marble ) = 0.7474
Thus, we end up with ~75% chance of picking a red marble.
