Left Fingers

There are roughly 6,840,507,000* people in the world right now according to the population estimation clock. What would be your estimation if asked to multiply together the number of left fingers each person has?

(*as of January 1, 2012 according to World Bank)

Array of Letters

What is represented by this array of letters?

R       R
A
Y        Y

Crazy Eights

Using eight eights and addition only, can you make 1000?

Quad Cities

How many states can you name that contain only four letters?

The RiddleDude will start you off with two: Utah and Iowa.

How many more can you name?

Squared Squares

Imagine a grid comprising 20 X 20 squares. How many squares are there, of any size, in total?

Number Squared

What digit fills the ? in the last square?

4 5     6 7     8 9
2 0     4 2     7 ?

Cart before the Horse.

A horse is pulling a wagon up a hill at an increasing speed. Ignoring all masses except those of the horse and the wagon, which is the case (and why?):

a) the horse pulls on the wagon harder than the wagon pulls on the horse.
b) the horse pulls on the wagon less than the wagon pulls [...]

Lost Password

A man goes to work one day only to discover that he could not log on to his computer. His password doesn’t work. Then he remembers that the passwords are reset every month for security reasons. So he goes to his boss’s office and had this conversation:

Man: “Hey, boss, my password is out of date.”
Boss: [...]

Emperor’s New Clothes

What is represented by these letters?

S     U     I      T

Many Coins

A numismatist decides to divide his coin collection between his children. The oldest gets 1/2 of the collection, the next gets 1/4, the next gets 1/5, and the youngest gets the remaining 49 coins. How many coins are in the collection?