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Why We Need Decimals

Date: 10/23/95 at 15:52:9
From: Susan Yant

Why do we need decimals? 
   Toni Ceballos

Date: 11/12/95 at 16:29:26
From: Doctor Ethan

Hello Toni,
  You have asked a very good question.  

Decimals are very good for  many reasons. I will mention some, 
but there are many more.

1. They are easy to add.  
To add 1/5 and 1/2 you have to first find a common denominator.
That isn't too hard but it would be easier to add .2 and .5,
which (if you line up the decimal points) add just like normal 
numbers to .7 (which is 7/10).

2. They make it easy to see how big a number is.

If I asked you how big 227/95 was, you might not know 
right off. However, if I asked you how big  2.389 was you would 
know it is a little bigger than two.

These are two important reasons why we need decimals.

Hopefully as you study them more you will find more reasons on 
your own.

- Doctor Ethan,  The Geometry Forum

Associated Topics:
Elementary Fractions

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