A man takes a step forward with probability 0.4 and backward with probability 0.6. The probability that at the end of eleven steps, he is one step away from the starting point is
After 11 steps he is one step away when he takes 6 forward and 5 back, or 5 forward and 6 back.
P = \(\binom{11}{6}(0.4)^6(0.6)^5 + \binom{11}{5}(0.4)^5(0.6)^6\)
\(= 462\,(0.4)^5(0.6)^5\,(0.4 + 0.6) = 462\,(0.24)^5\)
Answer: (D)
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