Three people enter a room and have a green or blue hat placed on their heads. They cannot see their own hat but can see the other hats.
The colour of each hat is purely random. They could all be green, blue, or any combination of green and blue.
They need to guess their own hat colour by writing it on a piece of paper, or they can write 'pass'.
They cannot communicate with each other in any way once the game starts. But they can have a strategy meeting before the game.
If at least one of them guesses correctly they win $10,000 each, but if anyone guesses incorrectly they all get nothing.
What is the best strategy?

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

There is a square piece of paper with a hole that is denoted by the circle on the top right side in the given picture. You have to cut the paper in a manner that it forms two and only two separate pieces of paper and then rearrange the pieces in a manner that the holes come in the centre of the paper.

Can you solve the rebus below?

I never stop running even when I standstill. If I am formed by joining two identical bodies together, can you guess who I am?

The square root of number 121 is "11". What is the square root of the number "12345678987654321."?

Can you find the least possible number such that

If the number is divided by 3, it gives the remainder of 1;
If the number is divided by 4, it gives the remainder of 2;
If the number is divided by 5, it gives the remainder of 3;
If the number is divided by 6, it gives the remainder of 4.

A cat had three kittens: Snophy, Topsy and Jorden. What was the mother's name?

What has one letter and starts with an E?

When I go in I might cause pain. I cause you to spit and ask you not to swallow. I can fill your hole. What am I?