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Dear Friends,
Today I am going to describe divisibility of a number by 13. In
schools and coaching institutes students are taught divisibility of a
number by 2, 3, 4, 5, 6, 8, 9 and 11. I hope you are all aware of this.
A number will be divisible by 2, if it is an even number.A number will
be divisible by 3, if sum of the digits is divisible by 3 and so on
and so fourth... But what about 7, 13, 17, 19 and other odd numbers?
Our contemporary mathematics is silent on this. In Vedic Mathematics
we have solutions for all these (surprised?)
Let me introduce 13. [Operator of 13 is 4 How?** ]
Find whether 1001 is divisible by 13?
By seeing it is difficult to say.
Do the following operations:
1001= 100+1(last digit)*4(operator)= 104= 10+ 4 (last
digit)*4(operator)=26
Since 26 is divisible by 13 therefore, 1001 is divisible by 13.
What have we done here?
We seperated the last digit of the number, multiplied it by the
operator and added the result to the rest. This we did until we found
a managable number. Go ahead and test this!
Pradeep Kumar
Chief Trainer (Magical Methods)
B. Tech, MBA (IIM Bangalore)
www.magicalmethods.com

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I hope you would enjoy this.

S Vaidehi