What does this mathematical rebus means ?

Two girls were born to the same mother, on the same day, at the same time, in the same month and year and yet they're not twins. How can this be ?

How old is your son? asked a man to his neighbour. My son is five times as old as my daughter and my wife is five times as old as my son. I am twice as old as my wife whereas my grandmother, who is celebrating her eighty-first birthday is as old as all of us put together.

How old is the man's son ?

A man is found dead with a knife in his back When the investigation is done. A chair lays beside him and the forensic team finds moisture around the body.

If he committed suicide, how did he do it?

Replace each alphabet with the number (1-9) to make the below equation correct.

AB * C = DE - F = GH / I

Out of four images which one is the odd one out?

If you remove one from eleven, it becomes ten. If you remove one from nine, it becomes ten.

How is this possible?

I am a number I am not an odd number I am higher than 90 I am not higher than 100 If you subtract me from 100, you get nothing. What number am I?

What is the fewest number of coins that would be required in order to make sure each and every coin touches exactly three other coins?

What have one eye but still cannot see?