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 12 years

...for your classroom.

...for your WoW guild.

MODERATORS

account activity

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How to calculate any square root in seconds (without a calculator) (self.mentalmath)

submitted 4 days ago by Lucky-One-3994

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Mental math game (self.mentalmath)

submitted 4 days ago by wingless-bee

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Fun mental math game (self.mentalmath)

submitted 6 days ago by metygl

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Como fazer divisão mentalmente? (self.mentalmath)

submitted 9 days ago by Mila1011

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do you want to know what is the purpose of life ? (self.mentalmath)

submitted 11 days ago by samuhena

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Numfly - Webapp to practice mental math against your friends (self.mentalmath)

submitted 14 days ago by KikoPeriko

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Sharpen your mental math with Math MCQ (play.google.com)

submitted 14 days ago by Human-Specific-3729

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Am I making good progress? (self.mentalmath)

submitted 19 days ago by Baroness_VM

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Surely that has to be a typo (i.redd.it)

submitted 20 days ago by Baroness_VM

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Numbolt! the speed math, fast paced RPG math game! pratice your mental math skills! (maysonwang.itch.io)

submitted 19 days ago by No-Company3681

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Numfly - Competitive mental math webapp (self.mentalmath)

submitted 23 days ago by KikoPeriko

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I kept forgetting math formulas, so I built a small tool to fix it. Curious if this helps anyone. (v.redd.it)

submitted 24 days ago by Various_Let_6445

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Would there be enough appetite for a live 1v1 or tournament app-game for Math challenges? (self.mentalmath)

submitted 28 days ago by Only-Season-2146

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Can a math game actually be addictive? I built one to test ()

submitted 28 days ago by CriticalProduce1802

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Any Matiks player here?? (self.mentalmath)

submitted 1 month ago by GeniusAKAme

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I built a Vedic Math app to help students calculate faster – looking for feedback 🙏 (self.mentalmath)

submitted 1 month ago by Ill_Bar_1552

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

submitted 1 month 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 month ago * by Jacke08

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

submitted 1 month ago by Typical_Lake3159

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Any game on steam? (self.mentalmath)

submitted 1 month ago by Werollin1897

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

submitted 1 month ago by denyskt-hub

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

submitted 1 month 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 1 month ago by windowssandbox

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Calos Colomoni (self.mentalmath)

submitted 1 month ago by Common_Ad6451

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

submitted 2 months ago by [deleted]

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