A problem of Modular Arithmetic

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rakeen
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A problem of Modular Arithmetic

Unread post by rakeen » Sat Dec 18, 2010 10:25 am

Dividing a positive integer by 3 the residue becomes 1
by 4 the residue becomes 2
by 5 the residue becomes 3
by 6 the residue becomes 4

what is the residue if we divide the integer by 7 ?
r@k€€/|/

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Re: A problem of Modular Arithmetic

Unread post by AntiviruShahriar » Sat Dec 18, 2010 12:35 pm

$3a+1=n=4b+2 theke n1=10,22..........[10+g12]$ gpurnosongkha
$n1=5c+3 er jonno 58, 118.......{(5x-1)12+10}[n{1} hotee dhara toiri koree]$
${(5x-1)12+10} x=natural number$
eita ki thik ase????????????????

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Avik Roy
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Re: A problem of Modular Arithmetic

Unread post by Avik Roy » Sat Dec 18, 2010 4:33 pm

The numbers are of the form $60n+1$
There's no single residue when dividing by 7, can there be?
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Re: A problem of Modular Arithmetic

Unread post by Moon » Sat Dec 18, 2010 8:25 pm

AntiviruShahriar wrote:$3a+1=n=4b+2 theke n1=10,22..........[10+g12]$ gpurnosongkha
$n1=5c+3 er jonno 58, 118.......{(5x-1)12+10}[n{1} hotee dhara toiri koree]$
${(5x-1)12+10} x=natural number$
eita ki thik ase????????????????
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Re: A problem of Modular Arithmetic

Unread post by Muhiminul Maruf » Sat Dec 18, 2010 8:38 pm

suppose the integer is X,then
X _= 1 (mod 3)................1
X _= 2 (mod 4)....................2
X _= 3 (mod 5)........................3
X _= 4 (mod 6)............................4


but how can i make a relation with these four equation??????????? :roll: :roll: :roll: :shock: :shock:

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Re: A problem of Modular Arithmetic

Unread post by Labib » Sat Dec 18, 2010 11:51 pm

I think there's no definite residue!!!
it's 0,1,2,3,4,5,6.
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Re: A problem of Modular Arithmetic

Unread post by AntiviruShahriar » Sun Dec 19, 2010 1:15 am

Avik Roy wrote:The numbers are of the form $60n+1$
There's no single residue when dividing by 7, can there be?
amar $60n-2$ ashche ken????

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rakeen
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Re: A problem of Modular Arithmetic

Unread post by rakeen » Sun Dec 19, 2010 11:04 am

@Anti tomar every line individually bujhchi. But 1ta line er sathe r ekta line er kono relation khuje pachi na. :(
@Avik if we take n=1 , then 61 is not divisible by 7. the residue becomes 5. and if I consider Anti's result, for n=1 it is 58. and 58|7 .
@Maruf I also tried that way. But I need same modulo (mod x) for each of the equation to set up a relation. Generally we can guess it might be 5, for 7.
r@k€€/|/

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Avik Roy
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Re: A problem of Modular Arithmetic

Unread post by Avik Roy » Sun Dec 19, 2010 11:17 am

AntiviruShahriar wrote:
Avik Roy wrote:The numbers are of the form $60n+1$
There's no single residue when dividing by 7, can there be?
amar $60n-2$ ashche ken????
I'm sorry. I just misread the problem (which is quite common with me :cry: ). $60n-2$ is the correct one. However, that doesnt change the scenario much, sicne it still offers all available solutions
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Re: A problem of Modular Arithmetic

Unread post by AntiviruShahriar » Sun Dec 19, 2010 12:41 pm

rakeen wrote:@Anti tomar every line individually bujhchi. But 1ta line er sathe r ekta line er kono relation khuje pachi na. :(
@Avik if we take n=1 , then 61 is not divisible by 7. the residue becomes 5. and if I consider Anti's result, for n=1 it is 58. and 58|7 .
@Maruf I also tried that way. But I need same modulo (mod x) for each of the equation to set up a relation. Generally we can guess it might be 5, for 7.
asholee ami kono theory use kori nai....shorto dhoree dhoree agaisi r ans peye shetake dharay porinoto korsiii :ugeek:

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