A man is living at the 21st floor of his apartment building. When he wants to go out he takes the elevator to the ground floor but when he comes back home, he takes the elevator to the 15th floor and takes the stairs the rest of the way up.
The only time when he goes all the way up to the 21st floor with elevator is when there is somebody else in the elevator or sometimes if it is raining outside.
Why is this?
ANSWER:
The man is really so short and can not reach higher than the 15th floor button in elevator. But when there is somebody else in the elevator, they can hit the button for him to go 21st floor. When it is raining, he can use his umbrella to hit the buttons. Otherwise, he must take the stairs.
Brain Teaser Questions 