I am taken from a mine and shut up in a wooden case, from which I am never released, and yet I am used by almost every person. What am I?

I get hot but I never sweat,
I cook food but I am not a chef,
I have a door but you can't enter me,
I have a light but I am not a lamp.
Who am I?

How many people must be gathered together in a room, before you can be certain that there is a greater than 50/50 chance that at least two of them have the same birthday?

A dead body is found outside a multi-story multinational company. The case is reported and a homicide detective is called on the crime scene.

He looks at the body and then towards the building. From the position of the body, it is evident that the victim committed suicide. He goes to the first floor of the building and then walks in the direction of the dead body, opens the window and toss a coin in the air.

He goes to second floor and again repeats the process. He keeps doing this till he is done on all the floors. Then he returns back to the floor and tells his team that it is a murder.

How in heaven did he deduce that?

I am under you when I am whole.
I shift above you if you remove the first letter.
I come all around you if you remove the second as well.

Can you tell me who I am?

The day before yesterday I was 25 and the next year I will be 28. This is true only one day in a year. What day is my birthday?

Solve the equation by replacing the alphabet with numbers.

MOM + MOM + NO = BOOK=

A finger goes in me. You fiddle with me when you're bored. The best man always has me first. What am I?

The day after tomorrow will be three days before Tuesday. Can you find out what is today?

Two-person want to cross a river. Only one boat is present on the riverside that can carry only one person at a time.

However, they still manage to cross the river. How is it possible?