SOLUTION: In a box there are R red pens and B blue pens. Pens are randomly selected, one at a time, until a red one is obtained. Assume that each selected pen is replaced before the next one

Question 1025898: In a box there are R red pens and B blue pens. Pens are randomly selected, one at a time, until a red one is obtained. Assume that each selected pen is replaced before the next one is drawn. (a) what is the probability that you need to pick up a pen 3 times? (b) what is the probability that you need to pick up a pen at least 4 times?
Answer by Fombitz(32388) (Show Source): You can put this solution on YOUR website!
So find the probability that you get BBR.

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BBBR

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