Prove that twice of ten is the same as twice of eleven.

The Little ant seems to be always confused. Do you know why?

Sherlock Holmes was challenged to make a pre-drawn line smaller without erasing it. He did it in fractions of seconds. How?

What does this rebus mean?

O
N
C
E
TIME

I make a loud sound when I’m changing. When I do change, I get bigger but weigh less. What am I?

Which number should replace the question mark?

If six children and two dogs were under an umbrella, how come none of them got wet?

What does man love more than life, and hate more than death or mortal strife; that which satisfied men want; the poor have, and the rich require; the miser spends, the spendthrift saves, and all men carry to their graves?

Replace the question mark with the number below given a simple math problem.

When I got four, I have it none.
When I got two, I have it some.
When I got none, I have it all.

What is it?