# Talk:Short division

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## Used in computing.

I think the article should perhaps mention that this algorithm is used in computing to overcome limits on divide instructions in cpu's. See the book The Art Of Assembly, chapter 9.3.5 entitled "Extended Precision Division" (available freely online) where a 64 bit by 16 bit division is synthesized from four 32 bit by 16 bit divisions. Here's a link: [1]. 195.35.160.133 (talk) 15:46, 27 July 2010 (UTC) Martin.

Or maybe the article Division (digital) covers this? Unfortunately I find that article incomprehensable. But I added it to the see also list anyway. 93.95.251.162 (talk) 11:15, 10 August 2010 (UTC) Martin

## Layout

Putting the bar above the dividend was a sign of long division, it left space under the dividend for (possibly extensive) working. We were taught (England:1966) to put the bar under the dividend, thus leaving space above for carries:

${\displaystyle {\begin{matrix}4{\underline {)9^{1}5^{3}0.^{2}0}}\\\ \ 2\ 3\ 7.\ 5\\\end{matrix}}}$

Working this way was the foundation for factorising:

${\displaystyle {\begin{matrix}2{\underline {)950}}\\5{\underline {)475}}\\5{\underline {)\ 95}}\\\ \ \ 19\\\end{matrix}}}$

Younger readers might care to bear in mind that at that date the electronic calculator hadn't come into use and computers were big and expensive. Slide rules were only good for three digits, logs for four or five and so manual methods were the most accurate. Martin of Sheffield (talk) 13:13, 20 December 2012 (UTC)

## Modulo division

The new section ends ends:

At each step, one need not consider the quotient digits. Knowledge of the single-digit multiplication table allows us to think of the nearest multiple of the divisor and subtract without explicitly writing the quotient digit. For example, we know that 27 is 21+6 (or 28-1) so we find the intermediate remainder digit is 6, without needing to write the quotient 3. (emphasis added)

So, at each stage, you compute the quotient digit but do not write it. I don't see how this differs from computing the entire quotient and not recording it. — Arthur Rubin (talk) 18:18, 31 December 2012 (UTC)