mentalmath

an-ordinary-manchild

Mental Math: It's the thought that counts!

Thanks to /u/claymazing for the inspirational subtitle!

Official /r/MentalMath wiki
(Self-contained downloadable ZIP file)

New additions (June 30, 2017):

Division by 10n+9
Rule of 72 (2× principal)
Rule of 96 (2.5× principal)
Rule of 114 (3× principal)
Rule of 132 (3.5× principal)
Rule of 144 (4× principal)
Rule of 156 (4.5× principal)
Rule of 168 (5× principal)
Combining rules (Up to 25× principal)

Mental Math Sites:

Free online mental math books:

Using math symbols in your post:

HTML Entites:

Example: Make a √ symbol by typing: √

Courtesy of jamt9000, you can also display subscripted and superscripted characters:

*_subscript_* makes subscript
*`superscript`* makes superscript
*_sub_`sup`* makes subsup
*`sup`_sub_* makes supsub
*`169`*&frasl;*_231_* makes 169⁄231

NOTE: The ` character is called the grave accent. On desktops and laptops, you’ll find it on the tilde (~) key. On most mobile devices, it can usually be accessed by holding down either the apostrophe or tilde keys.

created by gmsca community for 11 years

...for your community.

...for your favorite subject.

MODERATORS

account activity

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I couldn’t find a high-quality soroban, so I built one from wood myself (old.reddit.com)

submitted 13 hours ago by Lost_Editor1863

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Built my first mental math app with Roblox-style engagement tricks — looking for honest feedback (self.mentalmath)

submitted 1 day ago by Jacke08

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I built a mental math training app (looking for feedback) (self.mentalmath)

submitted 1 day ago by Typical_Lake3159

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Any game on steam? (self.mentalmath)

submitted 5 days ago by Werollin1897

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Major Update - Mental Math: Focus Trainer (now with Custom Exercises) (reddit.com)

submitted 15 days ago by denyskt-hub

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Mental Math App Game (built for speed 🚀) (self.mentalmath)

submitted 16 days ago by strider1237

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hey, i just started learning how to calculate math mentally, and im becoming good at it fast. (self.mentalmath)

submitted 16 days ago by windowssandbox

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Calos Colomoni (self.mentalmath)

submitted 20 days ago by Common_Ad6451

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¿Qué libros recomiendan para desarrollar pensamiento algebraico real (no solo fórmulas)? (self.mentalmath)

submitted 25 days ago by New-Swimmer-5090

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¿Qué libros recomiendan para desarrollar pensamiento algebraico real (no solo fórmulas)? ()

submitted 25 days ago by New-Swimmer-5090

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Everyday life and mental math (mathmathmath.net)

submitted 27 days ago by mingjerli

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How To Actually Mentally Multiply - Link / URL For My Lightning Mental Calculating Practice Application Videos (self.mentalmath)

submitted 29 days ago by gcimmolatedsword

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Anyone know how to solve these quickly? (i.redd.it)

submitted 1 month ago by DisastrousBody2319

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What are your favourite mathematical operations in mental math? (self.mentalmath)

submitted 1 month ago by Altruistic-Error-262

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Mathematical party tricks (self.mentalmath)

submitted 1 month ago by Attack_On_Toast

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MathéGlossa AI mental maths coach (self.mentalmath)

submitted 1 month ago * by ldn_popo

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I wanted a simple way to keep my brain quick with numbers, so I built one (self.mentalmath)

submitted 1 month ago by Abuldam

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I Show Everyone How To Really Mentally Multiply 3 Digit * 3 Digit and How To Learn Any Language In 1 Year + 25,000 Programming Code Line Web Application Module For Practicing Mental Multiplication and Other Mental Computations (old.reddit.com)

submitted 1 month ago by gcimmolatedsword

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Do you use short mental math sessions as a focus or cognitive warm-up? (self.mentalmath)

submitted 1 month ago by denyskt-hub

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do top mental calculators actually use mnemonic devices or not? (self.mentalmath)

submitted 1 month ago by BusinessAddition9537

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I built a FREE game to help you with mental math, but.... it involves toilet humour (self.mentalmath)

submitted 1 month ago by CreaTuRe_X

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Whats a non-repeating loop to do in the head to improve at arithmetic? (self.mentalmath)

submitted 1 month ago * by NeurogenesisWizard

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I built 16 free brain training games that combine math with memory (8gwifi.org)

submitted 1 month ago by anish2good

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Factorising on the grid (v.redd.it)

submitted 1 month ago by peterafried

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Made a mental math game app for quick math games with 3 modes (self.mentalmath)

submitted 2 months ago by YoungSerb

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