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keshavdahiya
February 26th, 2006, 03:40 AM
CLICK HERE (http://www.digicc.com/fido/) & lets see how clever you are........;)
lemme know if you have a solution to this problem.....:D:p

fool4love
February 26th, 2006, 03:54 AM
CLICK HERE (http://www.digicc.com/fido/) & lets see how clever you are........;)
lemme know if you have a solution to this problem.....:D:p

kasutii cheezz thii.. keshav bhai!! arr solution to konya paya...:mad:

vinodks
February 26th, 2006, 10:44 AM
---- my post was wrong explanation so I erased it.....

-Vinod

onlyjat
March 25th, 2006, 09:06 PM
smart puuzzle but, still trouble understanding HOW it worked.:confused:

devdahiya
March 25th, 2006, 09:28 PM
Ghappo gya jelli sabh kei KASSAI.............tu konya sudhhre............? Ha..ha..ha..ha.

vinodks
March 25th, 2006, 10:01 PM
I GOT IT.

You take any no. and jumble its digit to get another no. Then subtract smaller no. from bigger no and get a no. say X.

FACT: If you make sum of all digits in X it has to be either 18 or 27. Verify. I'm working on general proof but its hard.

If you tell computer 3 digits, its trivial to guess the 4th one. If sum of 3 digits is less than 18, it will be subtracted from 18 to find 4th digit. If sum of X is more than 18, it will subtracted from 27 to get 4th one. (Its strange that sum of digits in X can't exceed 27, can be verified easily, proof is difficult though)

E.g.
If you got X=2088 (i.e. 3211-1123) and tell compu 8,0,2.... 4th digit is 18-(2+8)=8

Enjoy!
-Vinod

arunshamli
March 25th, 2006, 10:49 PM
I GOT IT.

You take any no. and jumble its digit to get another no. Then subtract smaller no. from bigger no and get a no. say X.

FACT: If you make sum of all digits in X it has to be either 18 or 27. Verify. I'm working on general proof but its hard.

If you tell computer 3 digits, its trivial to guess the 4th one. If sum of 3 digits is less than 18, it will be subtracted from 18 to find 4th digit. If sum of X is more than 18, it will subtracted from 27 to get 4th one. (Its strange that sum of digits in X can't exceed 27, can be verified easily, proof is difficult though)

E.g.
If you got X=2088 (i.e. 3211-1123) and tell compu 8,0,2.... 4th digit is 18-(2+8)=8

Enjoy!
-Vinod


no matter what number you select, the final number you get will always be a multiple of 9 and the computer knows it.

rest is simple

vinodks
March 25th, 2006, 10:59 PM
Ture. For a no of 3 or 4 digits its 18 or 27... Do you have proof for any number of digits?... it can be verified for couple of digits but do you have general analytical proof?

-vinod


no matter what number you select, the final number you get will always be a multiple of 9 and the computer knows it.

rest is simple

arunshamli
March 25th, 2006, 11:48 PM
Ture. For a no of 3 or 4 digits its 18 or 27... Do you have proof for any number of digits?... it can be varified for couple of digits but do you have general analytical proof?

-vinod


This is true for any digit number and not only for 3 or 4 digit numbers. in this particular puzzle you can start with any digit number and it will be able to give you the correct answer. aur ye jo 3digits ya 4 digits bolta hai ...woh sirf confuse karne ke liye.....

let me try to explain it


It is a well known fact that if a number is divisible by 9, sum of its digits will also be a divisible by 9.

Step 1.
let us take a 5 digits number whose digits are A ,B ,C ,D and E(you can take any number of digits if you want...here I am taking only 5 digits...later on you will see that number of digits does not matter at all)

The number will be 10000*A + 1000 * B + 100*C + 10*D + E

Step 2. if you shuffle its digits...and let us say you get the digits in this order E,A,D,C and B( the order does not matter, you can choose any other order)
the new number is 10000*E+1000*A+100*D+10*C+B

Step 3. Subtract these you get

(10000*A-1000*A) + (1000*B-B) +(100*C-10*C) + (10*D-100*D) + (E-10000*E)

9000A+999B+90C-90D-99999E
=9*(1000*A+111*B+10*C-10*D-11111*E)
and you can see it is clearly divisible by 9


and because this is divible by 9, sum of A, B C D and E will also be divible by 9

I hope this will help...I know this is not the best way to prove it, but you will get the idea.

vinodks
March 25th, 2006, 11:53 PM
Good Arun!... s**t! I was wasting my time in different corner of the room... and its so obvious. Keep it up

-vinod



This is true for any digit number and not only for 3 or 4 digit numbers. in this particular puzzle you can start with any digit number and it will be able to give you the correct answer. aur ye jo 3digits ya 4 digits bolta hai ...woh sirf confuse karne ke liye.....

let me try to explain it


It is a well known fact that if a number is divisible by 9, sum of its digits will also be a divisible by 9.

Step 1.
let us take a 5 digits number whose digits are A ,B ,C ,D and E(you can take any number of digits if you want...here I am taking only 5 digits...later on you will see that number of digits does not matter at all)

The number will be 10000*A + 1000 * B + 100*C + 10*D + E

Step 2. if you shuffle its digits...and let us say you get the digits in this order E,A,D,C and B( the order does not matter, you can choose any other order)
the new number is 10000*E+1000*A+100*D+10*C+B

Step 3. Subtract these you get

(10000*A-1000*A) + (1000*B-B) +(100*C-10*C) + (10*D-100*D) + (E-10000*E)

9000A+999B+90C-90D-99999E
=9*(1000*A+111*B+10*C-10*D-11111*E)
and you can see it is clearly divisible by 9


and because this is divible by 9, sum of A, B C D and E will also be divible by 9

I hope this will help...I know this is not the best way to prove it, but you will get the idea.

jitendershooda
March 26th, 2006, 12:13 AM
Good explanation Arun ...