# Poll: the sum(7,9)

Dan Shafer revdan at danshafer.com
Tue Mar 15 11:19:59 CST 2005

```I guess I'm one of those odd ducks who just memorized all this crap in
school. It never occurs to me to DO anything to solve this kind of math
problem. The answer just appears in my mind.

Dan the Mysterious

On Mar 15, 2005, at 6:38 AM, Jim Hurley wrote:

>>
>> What a fascinating question! I had to think for a minute to try and
>> analyze how I do that sort of mental arithmetic, but in the end I
>> realized what I do.
>>
>> I seem to have a visual stack that goes up to 10, so I put the 9 into
>> stack, then move 1 from the 7 to fill the stack, leaving me with 10 in
>> the stack and 6 left over. I guess this is #1 but with more of a
>> number-line visualization rather than fingers :-)
>>
>> HTH,
>> Sarah
>>
>
>
> Sarah,
>
> I am also digitally oriented. I envy those people with memories which
> allow them to simply snatch these results from their memory bank. Mine
> is bankrupt.
>
> I also apply a similar digital technique on subtraction. For example:
> subtract 9 from 17. Subtract 7 from 9 to get 2; that's easy. Then
> subtract 2 from 10 to get 8. Therefore 9 from 17 = 8. Pathetic I know.
> I have even forgotten portions of the mutilation table. My transition
> into senility is very smooth.
>
> (Do this with your fingers in you lap and you have a laptop computer.)
>
> Jim
> _______________________________________________
> use-revolution mailing list
> use-revolution at lists.runrev.com
> http://lists.runrev.com/mailman/listinfo/use-revolution
>

```