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- black and white balls in the box 3 answers
There are $B$ blue balls and $R$ red balls in a bag.
Now, randomly two balls are removed .
If both of them are of different color , then blue ball is added to the bag .
If both of them are of same color , then red ball is added to the bag .
Also the two drawn balls are discarded.
This is done until one ball is left.
What is the probability that the last ball is blue?
Now, I could not even start a solution on this , so could anyone provide help in solving this ?