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?

John can place six large boxes or nine small boxes into a carton.

Can you find out in how many cartons can he place sixty-six boxes in total?

A person is found murdered in his Chamber. When the crime scene is investigated, the Investigator find out that there is a calendar on which the victim has written a few numbers with his blood. The numbers are 4, 11, 11 and 4.

There are four suspects in the murder, John, Jacob, Anna and Lee. Can you find out who is the murderer?

I have a five and a three-gallon jar. Assuming there is an infinite supply of water, how can I measure one-gallon water?

our enemy challenges you to play Russian Roulette with a 6-cylinder pistol (meaning it has room for 6 bullets). He puts 2 bullets into the gun in consecutive slots, and leaves the next four slots blank. He spins the barrel and hands you the gun. You point the gun at yourself and pull the trigger. It doesn't go off. Your enemy tells you that you need to pull the trigger one more time, and that you can choose to either spin the barrel at random, or not, before pulling the trigger again. Spinning the barrel will position the barrel in a random position.

Assuming you'd like to live, should you spin the barrel or not before pulling the trigger again?

If we tell you that there is a relation between the numbers and letters in the given figure, can you analyze it and find the missing letter in the last box?

A pregnant woman is preparing to name her seventh child. Her children's names so far are Dominique, Regis, Michelle, Fawn, Sophie, and Lara. What will she name her next child -- Jessica, Katie, Abby or Tilly?

That attorney is my brother, testified the accountant.

But the attorney testified he didn't have a brother.

Who is lying?

If it took eight men ten hours to build a wall, how long would it take four men to build it?

In the addition below, all digits have been replaced by letters. Equal letters represent equal digits and different letters represent different digits.
ABCABA
BBDCAA
ABEABB
ABDBAA
------- +
AAFGBDH
What does the complete addition look like in digits?