A man takes astep forward with probability 0 4 and backward with probability 0 6 find the the probability that - Maths - Probability

Question

A man takes astep forward with probability 0 4 and backward with
probability 0 6 find the the probability that at the end of eleven
steps he is one step away from the starting point

Priyanka Kedia · Accepted Answer

Let a step forward be a success and a step backward be a failure
Then, the probability of success in one step=p=0 4=410=25And, the
probability of failure in one step=q=0 6=610=35In eleven steps he
will be one step away from the starting point if the number of
successes andfailures differ by 1 So, the number of successes=6,
and the number of failures=5or the number of successes=5, and the
number of failures=6Thus, the required
probability=C611p6q5+C511p5q6=C611256355+C511255356=11!6!5!25535535+25=462×6255

A man takes astep forward with probability 0.4 and backward with probability 0.6 find the the probability that at the end of eleven steps he is one step away from the starting point