An urn contains 6 black balls and 5 white belle. Harry randomly picks balls from the urn until he picks out a white ball. At this point he stops...

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An urn contains 6 black balls and 5 white belle. Harry randomly picks balls from the urn until he picks out a white ball. At this point he stops drawingballs. What is the probability that harry picks out at most 2 black balls. Remember you can enter expressions into the answer box, this will allow you to avoid the use of a calculator.