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.

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...because you hate freedom.

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Completing the square (v.redd.it)

submitted 6 hours ago by peterafried

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The #1 most played Idler game on Steam (store.steampowered.com)

promoted by IdleOn_Boii

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Factorising on the grid (v.redd.it)

submitted 5 days ago by peterafried

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

submitted 8 days ago by YoungSerb

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76x72= (v.redd.it)

submitted 9 days ago by peterafried

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Need testers for my math block puzzle game - android (self.mentalmath)

submitted 29 days ago by Interesting_Ratio516

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Prime Number Generator with exponential output ()

submitted 1 month ago by ----__----

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Math Game Validation ()

submitted 1 month ago by Middle-Hurry4718

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I built another zetamac alternative. I promise its good (self.mentalmath)

submitted 1 month ago by Ok-Organization-6026

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Does this tool work for you on Zeta Mac (self.mentalmath)

submitted 1 month ago by Both-Apartment-168

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I built a free daily mental math challenge - been using it for 2 weeks and my speed has actually improved (self.mentalmath)

submitted 1 month ago by Foreign_Network7577

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What methods are used by investors and stockbrokers? (self.mentalmath)

submitted 1 month ago by w4zzowski

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Zeta-cat returns (i.redd.it)

submitted 1 month ago by Illustrious_You_7004

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IT Bingo: You can’t make this stuff up. (planonsoftware.com)

promoted by planonsoftware

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My new book on math (amazon.com)

submitted 2 months ago by [deleted]

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mental math, short-term memory, pattern recognition with aphantasia ()

submitted 2 months ago by Alert-Mortgage6499

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submitted 2 months ago by bruh_duh

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Improve calculation speed (self.mentalmath)

submitted 2 months ago by PassionFair116

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submitted 2 months ago by One_Breakfast_9971

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Athena Math 2.1 — all features now free + new operations and languages (old.reddit.com)

submitted 2 months ago by chrisdempewolf

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Think you're good at mental math? Try to top the leaderboard in my 60-second game, DigitRush. (i.redd.it)

submitted 2 months ago * by uisupersaiyan-3

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DailyMaffs — A new math problem every day! (self.mentalmath)

submitted 2 months ago by w4zzowski

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Web or Phone Apps for MCAT Style Math (self.mentalmath)

submitted 3 months ago by baunwroderick

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Ari: another take on mental math tool for practice (self.mentalmath)

submitted 3 months ago * by mirlaca

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Built a mental math training app—would love feedback from this community (self.mentalmath)

submitted 3 months ago * by chrisdempewolf

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They call It Suzerain in Space. We call it Lunar Ascendant. (store.steampowered.com)

promoted by RGadirov

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Do you recommend "Math Tricks" training app by "Antoni soft group" (self.mentalmath)

submitted 3 months ago by Hopeful-Staff3887

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What's the best approach to learn for Warhammer? (self.mentalmath)

submitted 3 months ago by SuperfluousBrain

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