# [Edu-sig] Re: reducing fractions

**Steve Litt
**
slitt@troubleshooters.com

*Fri, 15 Sep 2000 11:14:50 -0400*

At 12:41 PM 8/14/00 -0700, Kirby Urner wrote:
>*"Janet Johnson" <johnsonje@adelphia.net> wrote:
*>*
*>>*I teach 6th grade and every year my students seem to have a lot of
*>>*difficulty with fractions, specifically, reducing or recognizing that a
*>>*fraction isn't reduced. I have given them many ideas on how to tell, even
*>>*to the point of writing out the factors for both the numerator and
*>>*denominator. Does anyone have any suggestions on how to get this concept
*>>*across to the students? Any suggestions would be greatly appreciated.
*>>*Janet Johnson
*>*
*>*You could unsimplify some fractions e.g. 2/3 -> 10/15
*>*i.e. show the inverse of what it means to "simplify".
*>*
*>*If 'prime number' is already a concept, you could try
*>*'relative prime' meaning no factors in common (i.e.
*>*"a fraction is in lowest terms when the numerator and
*>*denominator are both integers and are relative primes").
*>*
*>*Along these lines, I really like your idea of writing
*>*out the prime factors, crossing out those in common e.g.:
*>*
*>* 150/210 -> (3 x 5 x 2 x 5) / (7 x 3 x 2 x 5) -> 5/7
*
That's how my 7th grade teacher taught me to simplify fractions, and I've
never been sorry.
Steve Litt
Webmaster, Troubleshooters.Com
http://www.troubleshooters.com
slitt@troubleshooters.com