This puzzle is for Harry Potter fans. Do you know why Tom Riddle is called Lord Voldemort?

A mother is 21 years older than her child. In exactly 6 years from now, the mother will be exactly 5 times as old as the child.
Where's the father?

How high do you have to count before you use the letter “a” in the English spelling of the whole number?

John was piloting a plane behind a car but was never able to overtake it. Why?

Jigsaw captured 100 people and make them stand in a circle and all these people are labelled as Person1, Person2, Person3... Person100. He made them play a crazy game in which Person 1 shot Person 2 and pass the gun to the next person and so on until one stands alive.

Which person will survive in the end?

What has hands, but can’t clap?

Why do we preferably have round manhole covers and not square ones?

I possess a head

I flaunt a tail

But I don't have mouth or legs

Can you find out who I am?

Once upon a time, there was a castle on a square island. The entire island was surrounded by a 14m wide trench. The Romans had wanted to invade the castle and had brought a few wooden planks along with them to facilitate themselves in crossing the moat. The planks were however found to be only 13m long.

The Romans still managed to cross the trench. How did they do it?

What is the four-digit number in which the first digit is one-third the second, the third is the sum of the first two, and the last is three times the second?