Replace the question mark with the number below given a simple math problem.

See the given image carefully. What you have to do is move the blue checkers in the position of the black checkers and vice versa. You are only allowed to move the checker to an adjacent empty space. Do it in the least possible moves.

What always comes into a house through the keyhole?

During an experiment, a guy throws a bouncy ball from a 100 feet tall building. The ball has a specific characteristic. Every time it hits the ground, it bounces up halfway.

How many bounces do you think the ball will make before it comes to a stop ?

How many times can you subtract the number two from the number fifty?

Find The Missing Number In the Sequence.
6 25 64 ? 32 1

Can you count the number of seconds in a year?

Clue: You need to bother about calculation.

John and Jacob are twin brothers. One of them is a liar whereas the other one is a truth-teller.

I called their home number and one of them picked up.
I asked. 'Does John lie?' The person replied with a yes.

Whom did I talk with, John or Jacob?

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

Begin with a word, five letters to my name,
Remove the first and last but I am the same
Take out my middle and still, I remain.
What word am I?