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

The Puzzle: A girl, a boy, and a dog start walking down a road.

They start at the same time, from the same point, in the same direction.

The boy walks at 5 km/h, the girl at 6 km/h.

The dog runs from boy to girl and back again with a constant speed of 10 km/h. The dog does not slow down on the turn.
How far does the dog travel in 1 hour?

I live in a bowl. I can swim. I have a tail. I also have fins and big eyes. What am I?

How can you write nineteen in a manner that if we take out one, it becomes twenty?

In my garden, I have many trees but only one of them is the mango tree. In these mango trees, there are some mangoes(as expected).

But after a strong wind, there are neither mangoes on the tree nor on the ground. Explain?

Two men play a dice game involving roll of two standard dice. Man X says that a 12 will be rolled first. Man Y says that two consecutive 7s will be rolled first. The men keep rolling until one of them wins.

What is the probability that X will win ?

Can you make a six-letter word using the letters N, A and B ?

I noticed one of the words in the oxford dictionary is spelled incorrectly. What about you?

All of the flowers I have are orchids except two. All of the flowers I have are hibiscuses except two. All of the flowers I have are roses except two.

Can you tell me how many flowers I have?

Find the missing letter in the last circle logically in the given below picture.