If it took eight men ten hours to build a wall, how long would it take four men to build it?

When my father was 31 I was 8. Now he is twice as old as me. How old am I?

What 5-letter word typed in all capital letters can be read the same upside down?

Find the next number in the sequence

1, 2, 6, 21, 88, __?

I’m tall when I’m young, and I’m short when I’m old. What am I?

French Police inspects a room where there are no windows, no doors, no tables and is almost empty expect there is just a puddle of water. They found a dead man who obviously hung herself from the ceiling, but they are not able to figure out how this had happened.

John and Jacob entered the crime scene and easily able to solve the case.

How did the man die?

Two natural numbers have a sum of less than 100 and are greater than one.

John knows the product of the numbers and Jacob knows the sum of numbers.

The following conversation takes place between them:
John: 'I am not aware of those numbers.'
Jacob: 'I knew you wouldn't be. I am not aware myself.'
John: 'Now I know them!'
Jacob: 'Now I know them, too!'

What are the two numbers?

I know a nine-letter word having only one vowel.
Do you ?

What three numbers, none of which is zero, give the same result whether they’re added or multiplied?

In a boat, the father of a sailor's son is sitting with the son of the sailor. However, the sailor is not present on the boat.

Can this even be possible?