Question

b) There are 6 floors in the downtown campus JSR building. In the morning several people get on the elevator on the first floor. The button for every floor (second through sixth) is lit (because a student will get off there). How many people must be on the elevator to insure that at least two people get off on the same floor?

Answer 1

6

Explanation:

There must be at least one more person than the number of possible stops. The elevator is scheduled to make 5 stops (at floors 2, 3, 4, 5, 6), so there must be at least 6 people on board to ensure 2 get off at the same stop.