While staying in a 15-story hotel, Polya plays the following game. She enters an elevator on the floor. She flips a fair coin five times to determine her next five stops. Each time she flips heads, she goes up one floor. Each time she flips tails, she goes down one floor. What is the probability that each of her next five stops is on the floor or higher? Express your answer as a common fraction.
Well if you are in a hurry then that imples you are only really interested in the answer.
Hence there is little reason for any of us to answer.
I am only interested in helping you to learn. I am not interested in providing you with a quick answer so that you can scrible it down, and then go off to do something more fun.