A man lives on the fifteenth floor of an apartment building. Every morning he takes the elevator down to the lobby and leaves the building. In the evening, he gets into the elevator, and, if there is someone else in the elevator, or if it was raining that day, he goes back to his floor directly. Otherwise, he goes to the tenth floor and walks up five flights of stairs to his apartment. Can you explain why he does this?

What type of tree can I carry in my hand?

John killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?

Prove that twice of ten is the same as twice of eleven.

Which is the smallest number that you can write using all the vowels exactly once?

Can anyone tell me a word in the English dictionary which has a silent 'z'?

Which is faster, Heat or Cold ? Explain.

I know there are two methods by using three time the same number with a plus(+) operator , you can make sum as 60.

One of them is 20+20+20.

whats the other way ?

On a magical land of Mexico , all the animal in the land are rational.

There are 10 tigers and one goat.
Tiger can eat goat but since it's a magical land , the tiger who eats the goat , turns into goat and then can be eaten by the remaining tiger(s).

If we leave them for some time then how many goat and tiger will be there , when we come back ?

What does it mean?