You need to arrange three 7 and mathematical symbols to form number 1?

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

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

John is the son of Jacob.
So,
Jacob is the_____of John's father?

How can I get the answer 24 by only using the numbers 8,8,3,3?

You can use the main signs add, subtract multiply and divide.

They came out at night, without being called.
They lost at day, without being stolen.
Who are they?

Can you find a seven digit number which describes itself. The first digit is the number of zeros in the number. The second digit is the number of ones in the number, etc. For example, in the number 21200, there are 2 zeros, 1 one, 2 twos, 0 threes and 0 fours.

A pack of cards has 40 cards. You are blindfolded. Out of 40, 25 cards are facing down while 15 are facing up. You have been asked to divide this pack of cards into two decks - so that each deck contains an equal number of face-up cards. Remember, you are blindfolded.

How will you do it?

Only one colour, but not one size,
Stuck at the bottom, yet easily flies.
Present in sun, but not in rain,
Doing no harm, and feeling no pain.
What is it?

Place the numbers from 1 to 9 in the circles in a manner that each side of the triangle sums up to 17.