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A comment on Testing for Divisibility by 19.

Re:Testing for Divisibility by 19 by 8bitsrule on Monday November 23, 2020 @09:54AM (#25187291)
In some cases its quicker to think of a larger number that's a multiple of 20, then subtract the multiple,

E.g. 228? 240 = 12x20, 240-12 = 228.

2337? 2360 = 118x20.

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Re:Testing for Divisibility by 19 by imheretolearn on Monday November 23, 2020 @11:31AM (#25188477)
The correct way would be to subtract multiple*diff from the answer of the first multiplication.

I couldn't point to a reason but I have been using this method since childhood without being taught :)

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Re:Testing for Divisibility by 19 by onlyrealcuzzo on Monday November 23, 2020 @10:46AM (#25187942)
This is similar to Vedic math, right?

https://en.wikipedia.org/wiki/Vedic_Mathematics

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