perplexus.info :: Probability : Red and Yellow

Red and Yellow (Posted on 2024-04-16)

A bag contains an unknown number of red balls and yellow balls. When N balls are drawn at random (without replacement) the probability that they are all yellow is 1/2. The number of balls in the bag is the minimum for this to happen.

If the first N balls were all yellow, what is the probability that the next ball drawn is red?

Express the probability as a function of N.

See The Solution Submitted by K Sengupta

Rating: 4.5000 (2 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)

re: some exceptions

| Comment 5 of 7 |

(In reply to some exceptions by Charlie)

Those sporadic ones are interesting. 1<r<y

Are they part of a broader pattern?

Posted by Jer on 2024-04-17 10:10:44

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