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?

What can run but never walk, have a mouth that never speaks, have a head that never weeps, and have a bed but never sleeps?

My friends called me Iron59 because my parents are a chemist and a mathematician. What is my real name?

A wooden log balances equally on the scales when weighed with three-quarters of a pound and three-quarters of a wooden log.

Can you calculate the weight of the entire wooden log?

How much will a 38° angle measure when looked at under a microscope that magnifies ten times?

Can you make a six-letter word using the letters N, A and B ?

In particular commonwealth games, a female participant won silver and gold medals for a single event.

How can this be possible?

I have two coins.
* One of the coins is a faulty coin having a tail on both sides of it.
* The other coin is a perfect coin (heads on side and tail on other).

I blindfold myself and pick a coin and put the coin on the table. The face of the coin towards the sky is the tail.

What is the probability that another side is also tail?

What work can one never finish?

What makes this number unique: 8,549,176,320?