Comments on: 3 Quick and Dirty Business Hacks

By: Ankit Agarwal

Ankit Agarwal — Thu, 06 Aug 2009 12:55:09 +0000

I think that these were a few very basic tricks that he shared. There are many more such tricks in Vedic Maths.

By: courtney benson

courtney benson — Wed, 05 Aug 2009 02:02:48 +0000

Absolute nurds or Where were my math teachers heads when I went to school. I would have loved MATH if only I had this introduction. Hopefully, children will get to learn how much fun it can be to learn math – especially women.

By: Jacob Taylor

Jacob Taylor — Mon, 03 Aug 2009 19:03:46 +0000

Check some more tutorials at http://vedicmathsindia.org/tutorials.htm

By: R G

R G — Mon, 03 Aug 2009 14:39:59 +0000

Your mother sounds like a very smart teacher. Wish I had her growing up in the bronx. Maybe I would be understand what you are saying. LOL

By: Dave Truslow

Dave Truslow — Mon, 03 Aug 2009 03:37:44 +0000

Thanks. You might find the Trachtenberg system useful too. Devised to keep his sanity while a Nazi concentration camp prisoner. Subsequently used to teach math skills to children with learning disabilities.

Interesting background on the method – See http://www.speed-math.com/story.htm

By: 3 Quick and Dirty Business Hacks | Bookmarks

3 Quick and Dirty Business Hacks | Bookmarks — Sun, 02 Aug 2009 19:29:42 +0000

[...] Excerpt $(function(){ $("#startbox").html("My mother was a high school mathematics teacher and understood that kids learn best when learning is fun, so at a very young age she started teaching me math “tricks.” In the second grade she showed me how 9 times any number less than 10 was simply that number minus 1 concatenated with the sum of difference plus whatever it takes to get back to 9. For example, 9 x 8 is 8 minus 1 (7) concatenated with 9 minus 7 (2) — 72. I was hooked.Since then I have been fascinated with finding quick and dirty tricks to arrive at answers (or good approximations) to everything from the probability that my beloved Arizona Wildcats basketball team will win a game to market sizes and rates of return. Below are three of my favorite business hacks.Continue… [...]

By: A Good Primer on the Rule of 72 « The Reformed Broker

A Good Primer on the Rule of 72 « The Reformed Broker — Sun, 02 Aug 2009 17:44:40 +0000

[...] 3 Quick and Dirty Business Hacks (GigaOM) [...]

By: Kevin Marshall

Kevin Marshall — Sun, 02 Aug 2009 16:30:42 +0000

Awesome and interesting post…here’s another, I think easier to remember, trick about multiplying by nines…hold your ten fingers up, put down the finger you are multiplying by…the fingers to the right is first digit, the fingers to the left is the second digit…it’s hard to explain in text, but very simple visually to understand ( for example, say 9 * 8, so hold both hand in front of your face, bend down the middle finger on your left hand…the fingers to the right will be 7, and the fingers to the left will be 2…so your answer is 72).

By: Gillian Verga

Gillian Verga — Sun, 02 Aug 2009 15:41:30 +0000

Hi Mike,
You (or your kids) might like this book: “Thirty Days Has September: Cool Ways to Remember Stuff” by Chris Stevens. It has the nines and the elevens tricks, other cool math tricks plus chapters on spelling, history, grammar, etc.
It doesn’t have any Excel tricks, nor does it mention that being able to do math approximations quickly is a great way to advance a business discussion. You get credit for those points!

By: Michael Ni

Michael Ni — Sun, 02 Aug 2009 14:45:23 +0000

4 years at MIT and all I needed was goal seek! Nice post.

By: hokya

hokya — Sun, 02 Aug 2009 14:43:04 +0000

wow, this is helpful, i ask your permission to bookmark this page :-)

By: Mark Panay

Mark Panay — Sun, 02 Aug 2009 14:32:15 +0000

No problem. It amazes me that schools don’t teach this stuff to kids. The fact that my 9 year old can do any square up to 100 or divide any larger number by a single digit in his head freaks out his teachers instead of impressing them… Really makes you wonder.

Here’s another cool link to see the “magic” http://www.vedicmaths.org/Introduction/Tutorial/Tutorial.asp

For teaching kids, two books that are good are “The Cosmic Computer” and “Vedic Mathematics for Schools”.

Think I might write a post about this so I don’t take up any more of these comments. :)

By: Mike Speiser

Mike Speiser — Sun, 02 Aug 2009 14:22:09 +0000

Awesome link. Thanks Mark.

By: Mark Panay

Mark Panay — Sun, 02 Aug 2009 07:46:52 +0000

Very interesting hacks. Thanks.

Point 1 – “Mathemagic” – A lot of these are from Vedic Maths, thousands of years old Indian/Hindu maths… They invented the zero so have a good pedigree… Amazing system goes all the way to calculus and beyond… Not so much tricks as a complete maths system – http://hinduism.about.com/od/vedicmaths/a/what_is_vedic_math.htm

My kids love it. Thanks for the excel hacks…