Question

B)There are 2 white balls in bag A and 3 red balls in bag B. At each step of
the process, a ball is selected from each bag and the two balls selected
are interchanged. Let the state ai of the system be the number i of red
balls in bag A.Solve the probability that there are 2 red balls in A after 3
steps.

Answer 1

Answer:

It is equal to .7 = .82 + .2 × .3 and, of course, one does not need to calculate all ... Let ψ(k) be the expected number of steps till state m is ... Thus, keep them always in your bag