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?

You need to remove two matchsticks to make the below equation true. Can you do it ?

Different lights make me strange by changing me into different sizes. What am I?

Given that

(78)^9 = 6
And (69)^4 = 11

Can you find out

(99)^2 =?

(Note: This is Logical, not Mathematical)

Can you make four (4) nines (9) equal 100?

What is the Surname of Barbie Doll?

The answer I give is yes, but what I mean is no. What was the question?

Why is it very easy to weigh a fish?

Can you find a seven digit number which describes itself. The first digit is the number of zeros in the number. The second digit is the number of ones in the number, etc. For example, in the number 21200, there are 2 zeros, 1 one, 2 twos, 0 threes and 0 fours.

If we add four times the age of John four years from now to five times his age five years from now we get ten times his current age.

How old will John be two years from now?