A box initially contains two red balls and two blue balls.
Chapter 2, Problem 2.9.3(choose chapter or problem)
A box initially contains two red balls and two blue balls. At each turn, one of the balls within the box is selected at random and then replaced together with another ball of the opposite color. (a) After three turns, what is the distribution of the number of red balls in the box? (b) After three turns, what are the expectation and variance of the number of red balls in the box? (c) Repeat parts (a) and (b) if at each turn the selected ball is replaced with a ball of the same color.
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