From: Loyd <loydlin@aol.com>
To: Teacher2Teacher Public Discussion
Date: 2005030115:42:56
Subject: Re: Re: multiplication



Joan:  That technique is neat.  That is the first time I ever saw
that.  However, it is not to good when the numbers on the right are
large (10-the number) but it still works but may get into negative
numbers. The number on the lefe is the number of tens:

For example:  One that works:

9    1
7    3   (9-3 and 7-1=6)
------
6    3          6 tens + 3=63


Try this one: 

5   5

4   6
---------
-1    30  here you have to consider 4-5=-1 or actually -10.

-10 + 30 = 20.  

I am not sure that a 3, 4 or 5th grade student can use this to great
value.  But it does work for some of the harder ones.

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