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Division Problem


Date: 12 Jul 1995 12:05:57 -0400
From: Chris Santini
Subject: division

Question: What is eighty divided by one hundred?


Date: 13 Jul 1995 22:54:01 -0400
From: Dr. Ken
Subject: Re: division

Hello there!

To do division, we can write the two numbers on top of each other, like this:

   80
  ----
  100

When we write division like this, we can check to see whether there are any
numbers that divide both the top (numerator) and the bottom (denominator).
In this case, we can see from the "0" at the end of both the 80 and the 100
that 10 divides both numbers.  When that happens, we can get rid of it in
both the top and the bottom by dividing by it.  We're left with:

   8
  ---
  10

Are there any more factors?  Yup.  Both of the numbers are divisible by 2.
So let's divide both of them by 2.  We get:

  4
 ---
  5

Four fifths!  One answer to your question is that 80 divided by 100 is
four fifths.  Another way of writing four fifths is .8, and the way you say
that is either "point eight" or "eight tenths."  Notice that the fraction we
had before we got four fifths was eight tenths.  Pretty neat, huh?
  
-K
    
Associated Topics:
Elementary Division

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