i took this one from a newly created social network (madina) it was exiting and nice so thought of sharing it will all...hope u will like this new way of calculation...

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Chapter 0

Quick Tricks:
Easy (and Impressive) Calculations


In the pages that follow, you will learn to do math in your head
faster than you ever thought possible. After practicing the methods
in this book for just a little while, your ability to work with
numbers will increase dramatically. With even more practice,
you will be able to perform many calculations faster than someone
using a calculator. But in this chapter, my goal is to teach
you some easy yet impressive calculations you can learn to do
immediately. We’ll save some of the more serious stuff for later.


INSTANT MULTIPLICATION

Let’s begin with one of my favorite feats of mental math—how
to multiply, in your head, any two-digit number by eleven. It’s
very easy once you know the secret. Consider the problem:
32× 11
To solve this problem, simply add the digits, 3 + 2 =5, put
the 5 between the 3 and the 2, and there is your answer:
35×2
What could be easier? Now you try:
53 ×11
Since 5+ 3 = 8, your answer is simply
583
One more. Without looking at the answer or writing anything
down, what is
81×11?

Did you get 891? Congratulations!
Now before you get too excited, I have shown you only half
of what you need to know. Suppose the problem is
85 ×11
Although 8 + 5 = 13, the answer is NOT 8135!
As before, the 3 goes in between the numbers, but the 1 needs
to be added to the 8 to get the correct answer:
93×5
Think of the problem this way:
1
835 +
=935

2 Secrets of Mental Math
Here is another example. Try 57 × 11.
Since 5 + 7 = 12, the answer is
Okay, now it’s your turn. As fast as you can, what is
77 × 11?

If you got the answer 847, then give yourself a pat on the
back. You are on your way to becoming a mathemagician.
Now, I know from experience that if you tell a friend or
teacher that you can multiply, in your head, any two-digit number
by eleven, it won’t be long before they ask you to do 99 ×
11. Let’s do that one now, so we are ready for it.
Since 9 +9 = 18, the answer is:
Okay, take a moment to practice your new skill a few times,
then start showing off. You will be amazed at the reaction you
get. (Whether or not you decide to reveal the secret is up to you!)
Welcome back. At this point, you probably have a few questions,
such as:
“Can we use this method for multiplying three-digit numbers
(or larger) by eleven?”
1
989+
=1089

1
527+
=627

Quick Tricks: Easy (and Impressive) Calculations 3

Absolutely. For instance, for the problem 314×11, the
answer still begins with 3 and ends with 4. Since 3 +1 = 4, and
1 +4 =5, the answer is 3454. But we’ll save larger problems
like this for later.
More practically, you are probably saying to yourself,
“Well, this is fine for multiplying by elevens, but what about
larger numbers? How do I multiply numbers by twelve, or
thirteen, or thirty-six?”

My answer to that is, Patience! That’s what the rest of the
book is all about. In Chapters 2, 3, 6, and 8, you will learn methods
for multiplying together just about any two numbers. Better
still, you don’t have to memorize special rules for every number.
Just a handful of techniques is all that it takes to multiply numbers
in your head, quickly and easily.


TAKEN FROM MADINA.COM

PERRRFFFFEEECCCTTTTT..and easy

Thank you, Ilaf! That is, really fascinating!

I will look at more, of this! As I am terrible, at Maths! :-(