A mile-long train is moving at sixty miles an hour when it reaches a mile-long tunnel. How long does it take the entire train to pass through the tunnel?

There are 20 people in an empty, square room. Each person has full sight of the entire room and everyone in it without turning his head or body, or moving in any way (other than the eyes). Where can you place an apple so that all but one person can see it?

You are in a room that has three switches and a closed door. The switches control three light bulbs on the other side of the door. Once you open the door, you may never touch the switches again. How can you definitively tell which switch is connected to each of the light bulbs?

If a boy blows 18 bubbles,
Then pops 6 eats 7 and then
He pops 5 and blows 1.
How many are left?

That attorney is my brother, testified the accountant.

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

Who is lying?

I have cities, but no houses. I have mountains, but no trees. I have water, but no fish. What am I?

Irene killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?

The Puzzle: Here is a famous prize problem that Sam Loyd issued in 1882, offering $1000 as a prize for the best answer showing how to arrange the seven figures and the eight 'dots' .4.5.6.7.8.9.0. which would add up to 82

Can you write down eight eights so that they add up to one thousand?

I travel all around the world but always stay in the corner. What am I?