[GNC] Accounting trick

[Stan Brown (using GC 4.14)]

You're quite correct, R.

32 for 23 is a difference of 9, not 11. _Any_ swap of two digits will
make for a difference that's divisible by 9 (not necessarily equal to it).

52 for 25 is a difference of 27, 3×9. It's not a coincidence that the
digits 2 and 5 are 3 apart.

When dinosaurs ruled the earth and we kept ledgers manually, a
difference of say 630 in a trial balance told us to look for two
transposed digits in the 100s and 10s positions, with the digits 7 apart
because 63 = 9×7.

Stan Brown
Tehachapi, CA, USA
https://BrownMath.com

On 2025-12-22 09:52, R Losey wrote:
> Are you sure about that? I was told swapping numbers leads to a difference
> that is divisible by 9, not 11.
> 
> 
> 
> On Sun, Dec 21, 2025 at 3:39 PM Doug via gnucash-user <
> gnucash-user at gnucash.org> wrote:
> 
>>  There are some accounting tricks: number reversal usually gives a
>> difference divisible by 11 (not sure why!)