How is the moon similar to a dollar?

Assume there are approximately 5,000,000,000 (5 billion) people on Earth. What would you estimate to be the result, if you multiply together the number of fingers on every person's left hand? (For the purposes of this exercise, thumbs count as fingers, for five fingers per hand.) If you cannot estimate the number then try to guess how long the number would be.

Wednesday, Steve and Pam go to a restaurant to eat lunch. After eating lunch, they pay the bill. But Steve and Pam do not pay the bill. So…who does?

Decode below three cipher riddles:

26 L of the A
7 D of the W
1000 Y in a M

If you’ve got me, you want to share me; if you share me, you haven’t kept me. What am I?

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

This is a most unusual paragraph. How quickly can you find out what is so unusual about it? It looks so ordinary, you'd think nothing was wrong with it. Actually, nothing IS wrong with it. But it is not as ordinary as you might think. If you think about it for a bit, you will find out why it is truly so unusual. So what is it? What is so unordinary about this paragraph?

Three doctors said that Bill was their brother. Bill says he has no brothers. How many brothers does Bill actually have?

A Club organizes a Running Race, and John, Jacob, Minda, and Tony participated.

The results are as follows

John beats Jacob
Minda beats Toni
Toni beats John

Who came first in the race?

If I remove one from eleven it becomes Ten and if I remove one from nine also becomes Ten. How?