81 x 9 = 801. What must you do to make the this equation true?

What is the four-digit number in which the first digit is one-third the second, the third is the sum of the first two, and the last is three times the second?

Which is heavier: a ton of bricks or a ton of feathers?

No one wants to have it, but if one got it, he does not want to lose it. What is It?

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?

Forwards I am heavy, backward I am not. What am I?

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

It has horns but can’t beep. It is like to bleat but It is not a sheep. What is it?

Look at the below sequence of letters and tell us what the next letter should be:

O T T F F S S ?

If you’ve got me, you want to share me; if you share me, you haven’t kept me. What am I?