A man who was outside in the rain without an umbrella or hat didn’t get a single hair on his head wet. Why?

First, think of the colour of clouds. Next think the colour of snow. Last, think of the colour of the moon. Now, what do cows drink?

How many people must be gathered together in a room, before you can be certain that there is a greater than 50/50 chance that at least two of them have the same birthday?

There is one four-digit whole number n, such that the last four digits of n2 are the original number n

A Man gave one of his sons 10 cents and another son was given 15 cents. What time is it?
Hint: Figure out the relation between time and number, is not so easy..:)

Which number comes next in the number series?

2, 9, 30, 93, ?

A detective visits his friend John just to discover that John's neighbour Dr Jacob was murdered. Dr Jacob, who is a mathematician wrote the murderer's name in a code word "Hcqtfz". There were five suspects
1. Ajit
2. Pankaj
3. Ganpat
4. Deenu
5. Hariya

The Detective was instantly able to find the murderer.
Can you?

Can you find out which number multiplied by itself will give the output as 12345678987654321?

Look at the below sequence of letters and tell us what the next letter should be:

O T T F F S S ?

Take away my first letter, then take away my second letter. Then take away the rest of my letters, yet I remain the same. What am I?