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#1 2008-10-24 02:50:07
- tony123
- Member
- Registered: 2007-08-03
- Posts: 230
divisible
Prove that
is divisible by .Offline
#2 2008-10-24 03:42:35
- TheDude
- Member
- Registered: 2007-10-23
- Posts: 361
Re: divisible
The sum you posted is not divisible by 15, but it would be if you added 14^1987 to it.
Wrap it in bacon
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#3 2008-10-24 04:09:29
- tony123
- Member
- Registered: 2007-08-03
- Posts: 230
Re: divisible
no no no
The sum divisible by 15
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#4 2008-10-24 04:44:36
- mathsyperson
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- Registered: 2005-06-22
- Posts: 4,900
Re: divisible
I agree with TheDude.
Dividing each number by 15 and showing the remainder gives the sum as
1+8+12+4+5+6+13+2+9+10+11+3+7
This has a total of 91, which is not divisible by 15.
(Adding 14^1987 to the original sum would add 14 to the modified sum, making it 105 = 7*15)
Why did the vector cross the road?
It wanted to be normal.
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#5 2008-10-24 22:45:11
- tony123
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- Registered: 2007-08-03
- Posts: 230
Re: divisible
im so sory TheDude and mathsyperson I agree with you
yes i forget Adding 14^1987 to the original sum
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