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Topic: How would YOU simplify arithmetic?
Replies: 41   Last Post: Jul 11, 2012 12:56 AM

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 Paul A. Tanner III Posts: 5,920 Registered: 12/6/04
Re: How would YOU simplify arithmetic?
Posted: Jun 29, 2012 2:30 PM

On Fri, Jun 29, 2012 at 3:04 AM, Jonathan Crabtree <sendtojonathan@yahoo.com.au> wrote:
> PAUL thank you for your post on fractions provided in response to a post by Wayne. I appreciated your thoughts as downunder in Oz, four out of three kids get mixed up over fractions. <joke>
>

You are welcome. Please really give this method of fraction addition using the LCD shared in this thread
http://mathforum.org/kb/message.jspa?messageID=7841738
as a single equation full vetting. I believe that it will be viewed then as a very viable alternative as the usually taught way. Share this technique with everyone.

I always use three or more fractions to show how this single equation method makes part of fraction addition with the LCD easier, this part being going from a sum of many fractions to a single fraction.

When I illustrate this method I always use three or more fractions to how how superior it is to the usual way, since the more fractions there are to add, the easier this single equation method makes it easier toget to a single fraction . When I illustrate this method I always get the reaction along the lines of "why wasn't I showed that?"

And when I illustrate this method I always use three or more fractions, I use usually these three: 3/4 - 11/6 + 7/8. This usually terrifies those who have had problems in the past with LCD fraction addition, but when I use that aforementioned "m over the bottom times the top" approach and then use that simpler proof to show why it works, they have that "why wasn't I showed that?" type of reaction. That is, they see that once they have the LCD, it's a cinch using this single equation method to immediately go to a single fraction no matter how many fractions there are to be added - and this is in opposition to the usual way of LCD fraction addition, which becomes harder and harder when there are more and more fractions to add.

(Note: When I say "added" or "addition" I do mean to cover the operation of subtraction, but since in the usual number systems subtraction is adding the additive inverse I just say "added" or "addition" to cover both fraction addition and subtraction. In this single equation approach, in the numerator of the single fraction just copy the sign of the operator. When fully vetting this method you should see this.)