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.

Submitted by K Sengupta

Rating: 4.5000 (2 votes)

Solution: (Hide)

The required probability is 1/N.
Refer to the solution submitted by tomarken in this location.

Comments: ( You must be logged in to post comments.)

Subject	Author	Date
re(3): some exceptions	Brian Smith	2024-04-18 13:46:24
re(2): some exceptions	Brian Smith	2024-04-17 11:03:05
re: some exceptions	Jer	2024-04-17 10:10:44
re(2): some exceptions	Charlie	2024-04-17 07:48:18
re: some exceptions	Steve Herman	2024-04-16 16:31:21
some exceptions	Charlie	2024-04-16 15:24:43
Solution	tomarken	2024-04-16 13:51:55

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