Once while in his court, King Akbar asked Birbal to write something on a wall that makes one sad when read in good times and makes one happy when read in sad times.

He took only a few moment and wrote something that fit the requirements. What did he write?

Which three-digit number, made of consecutive digits, like 567, is 2 less than a cube and 2 more than a square?

A man embarked on a questionnaire game. He kept asking the same question to whomever he found. The answer each time was different.

Can you guess what the question was?

If you had a pizza with crust thickness 'a' and radius 'z', what's the volume of the pizza?

What came first, the chicken or the egg?

There are people and strange monkeys on this island, and you can not tell who is who (Edit: until you understand what they said - see below). They speak either only the truth or only lies.
Who are the following two guys?
A: B is a lying monkey. I am human.
B: A is telling the truth.

John can place six large boxes or nine small boxes into a carton.

Can you find out in how many cartons can he place sixty-six boxes in total?

In the four images below, can you find the odd one out?

Can you arrange four 9's and use at most 2 math symbols, to make the total 100?

using four eights (8) and a one (1) and one mathematical symbol , create the number 100