Name of program that helps do math in head quickly?

Question

It was on 20/20 or Dateline I think. A mathematician that is volunteering his skill in schools around the nation teaching kids ages elementary and up how to do math quickly in their head. The program didn' t show much of the methods, just said he could teach it in a matter of minutes. This guy was teaching 4th graders how to multiply 2 and 3 digits mentally.Also said he may decide to put the method on video or dvd soon. Does anyone know his name, or the name of a program that teaches you to do math in your head?

Answer 1

Mike's Math. Illinois based guy.
http://www.abcnews.go.com/2020/story?id=2690724&page=1

http://www.mikesmath.com/

if you did a search on any major search engine...yahoo for example and ran a search with the words "20 20 math" it would be the second link down.....try it out sometime....

Answer 2

I haven't seen the program, but I know the method, and you can teach yourself, if you wish.

Basically, you multiply "from left to right", adding as you go, instead of right-to-left.

For example, suppose you have the numbers 47 multiplied by 85:
47
x85
----
80*40 = 3200
+80*7 =.. 560
-----------------
..... ..... 3760
+40*5 =.. 200
-----------------
..... ..... 3960
+ 5*7 =..... 35
-----------------
..... ..... 3995

Three-digit numbers are a bit trickier because the "cross-multiplication" gets more involved. This time I'll use
436 x 427, and a slightly different presentation so I can keep track of what I'm doing without constantly scrolling:
436*427 = 400*400 + 400*30 + 20*400 + 400*6 + 20*30 + 7*400 + 20*6 + 7*30 + 7*6

436*427 =
400*400 = 160000 + 400*30 =
160000 + 12000 = 172000 + 20*400 =
172000 + 8000 = 180000 + 400*6 =
180000 + 2400 = 182400 + 20*30 =
182400 + 600 = 183000 + 7*400 =
183000 + 2800 = 185800 + 20*6 =
185800 + 120 = 185920 + 7*30 =
185920 + 210 = 186130 + 7*6 =
186130 + 42 = 186172

The key is maintaining the running total in your memory while you do the next step. It is actually easier than it looks, and becomes easier (and faster) with practice. Start with 2-digit numbers, and when you get comfortable with them, extend your prowess to 3-digit numbers.