Multiplication algorithm: Difference between revisions

Revision as of 05:10, 4 November 2017

Revision as of 14:04, 18 November 2017

Line 397:

47 x

————————————————

161 4884 94

920 1080 480

5629 23

————————————————

11371110 1131 587 94

————————————————

11371110 11 7 2

<nowiki>=================</nowiki> Answer: 11371110 ton 117 cwt 2 qtr

First multiply the quarters by 2, the result 94 is written into the first workspace. Next, multiply 12 x 47 but don't add up the partial results (4884, 1080480) yet. Likewise multiply 23 by 47. The quarters column is totalledtotaled and the result placed in the second workspace (a trivial move in this case). 94 quarters is 4823 cwt and 2 qtr, so place the 2 in the answer and put the 23 in the next column left. Now add up the three entries in the cwt column giving 1131587. This is 5629 t 117 cwt, so write the 117 into the answer and the 5629 in the column to the left. Now add up the tons column. There is no adjustment to make, so the result is just copied down.

The same layout and methods can be used for any traditional measurements and non-decimal currencies such as the old British [[£sd]] system.