## Saturday, May 15, 2010

### Math Tricks Everyone Must Know (math, education)

REVIEWED BY: Ms Cairo

MY RECOMMENDATION: Maybe

AMAZON SUBSCRIPTION LINK: Math Tricks Everyone Must Know

BLOG DESCRIPTION: Product Description
This teaches you how to use your mind like a math genius easily.

Example:

Concatenate a 3-digit number with itself (e.g. 835 -> 835835). Divide it by 7.
The reminder will be zero!

Exampple: 235235 / 7 = 33605

Now, divid the quotient by 11. The reminder will be zero!

Example: 235235 / 7 = 33605 -> 33605 / 11 = 3055

Again, divid the recent quotient by 13. The reminder will be zero!

Exampple: 235235 / 7 = 33605 -> 33605 / 11 = 3055 -> 3055 / 13 = 235

Where 235 is the original number!

Another example:

Take 743!
Concatenate it with itself: 743743
Divide it by 7: 743743 / 7 = 106249
Divide the quotient by 11: 106249 / 11 = 9659
Divide the recent quotient by 13: 9659 / 13 = 743

Why?

7 * 11 * 13 = 1001
Multiplying 1001 by any 3-digit number will be as concatenating it with itself:

100 * 1001 = 100100

945 * 1001 = 945945

So, any number that is obtained by concatenating a 3-digit number with itself can be divided by 1001 and as 1001 is equal to 7 * 11 * 13, it can be divided by 7, 11, and 13.

MY REVIEW: Well, the blog hasn't been updated since April 15, and its a brand new blog, so I'm not sure if I can give it a thumbs up or not... (In addition, for some reason the author chose to use a masthead that says, "The Diary of Osama Bin Laden." What's up with that?

If the author does return to it, it looks like it could be a fun blog. Whether or not he returns to it, that's the question. I'll keep an eye on it...

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