The probability that the first person goes to a movie that nobody else has already seen is 10/10=1. Then, the probability that the second person goes to a movie that nobody else has seen is 9/10, and similarly, for the third, 8/10. Repeating this process, the probability that nobody goes to a movie that has not already been seen is 10/10*9/10*8/10*7/10*6/10=.3024. Then, the probability that at least one person goes to a movie that has been seen already is 1-.3024=.6976.
