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

In the image given, you can find several triangles. Can you count them all?

You are in a land where thirty men and two women were dressed in classic black and white dresses.
They begin to fight as soon as any of them move.

Where are you?

A man died, leaving $10,000,000 for his widow, 5 sons and 4 daughters. Each daughter received an equal amount, each son received twice as much as a daughter, and the widow received three times as much as a son.

How much did the widow receive?

What is 3/7 chicken, 2/3 cat and 2/4 goat?

We have arranged an array of numbers below. What you have to do is use any kind of mathematical symbol you know excluding any symbol that contains a number like cube root. You can use any amount of symbols but you have to come up with a valid equation for all of them.

0 0 0 = 6
1 1 1 = 6
2 + 2 + 2 = 6
3 3 3 = 6
4 4 4 = 6
5 5 5 = 6
6 6 6 = 6
7 7 7 = 6
8 8 8 = 6
9 9 9 = 6

What jumps when it walks and sits when it stands?

This is a classy optical illusion puzzle. What more you can find except bricks in the image below?

They do not possess flesh or feathers or scales or bone
But still, they are blessed with fingers and thumbs of their own.

What can run but never walks, has a mouth but never talks, has a head but never weeps, has a bed but never sleeps?