# How to do divisions to many decimal places mentally?

**URL:** https://forum.artofmemory.com/t/how-to-do-divisions-to-many-decimal-places-mentally/30074
**Category:** Mental Calculation, Mathematics, and Puzzles
**Created:** [November 30, 2014, 7:17am UTC](https://forum.artofmemory.com/t/how-to-do-divisions-to-many-decimal-places-mentally/30074 "2014-11-30T07:17:19Z")
**Posts on this page:** 1
**Showing post:** 2

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### Author: ![Kinma](https://forum.artofmemory.com/letter_avatar_proxy/v4/letter/k/a88e4f/32.png) [@Kinma](https://forum.artofmemory.com/u/Kinma)
#### Post date: [November 30, 2014, 9:11am UTC](https://forum.artofmemory.com/t/how-to-do-divisions-to-many-decimal-places-mentally/30074/2 "2014-11-30T09:11:00Z")

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I have written about this here:

> **[Analyzing Rüdiger Gamms performance (division by 109)](https://forum.artofmemory.com/t/analyzing-rudiger-gamms-performance-division-by-109/28101)**
>
> While watching YouTube videos’of Rüdiger Gamms performance in order to find out how he does the higher powers I realized something. In at least three video’s I saw him do a division by 109. There is a reason for this. One example is this video: ...

And here:

> **[Division with 2 digits simultaneously!](https://forum.artofmemory.com/t/division-with-2-digits-simultaneously/29813)**
>
> When mentally dividing, sometimes it makes sense - speed wise - to do 2 digits at the same time. An example will make this clear, I hope. 100 / 37 If we were to divide by 40 as in 100 / 40 we immediately see 25 X 40 = 1000. So divide 1000 by...

After reading these pages you can do this as well!

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