Even and Odd Numbers

Date: 6/13/96 at 10:30:57
From: d'Hautree Modern Languages
Subject: Even and odd numbers

Dear Dr. Math,

Why do we have odd and even numbers?

Sharyn

Date: 6/18/96 at 13:49:52
From: Doctor Beth
Subject: Re: Even and odd numbers

I could answer you "we just do," but that wouldn't be very helpful!  
I don't know if anyone knows when the ideas of even and odd numbers 
started, but even the ancient Greeks thought about them a couple of
thousand years ago.

Numbers that can be evenly divided by two are even, and those that 
can't are odd.  Since every number can either be divided by two or 
not, every number is either even or odd.  The word "even" may come 
from the fact that it can be divided into two level or uniform (or 
"even") amounts.  For example, if you take a stack of 8 pennies, you 
can split them up into two level (or "even") stacks of four.  If you 
take 7 pennies, you can't divide them into two level stacks, and 
there's an "odd" one left over if you try, so you have an odd number.  

(I got the info on why the words are used from the book "The
Words of Mathematics" by Steven Schwartzman.)

-Doctor Beth,  The Math Forum
 Check out our web site!  http://mathforum.org/dr.math/