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Old 2006-08-08, 15:42   #1
mfgoode
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Cool Elevens!


a) Find the largest possible number containing any 9 of the 10 digits (0 included) which can be divided by 11 and leaving no remainder

b) Find the smallest possible number, with the same conditions, divisible fully with no remainder by 11

Eg: 896743012 (5 omitted). This is divisible by 11 but its neither the largest nor the smallest number.

Mally

Last fiddled with by mfgoode on 2006-08-08 at 15:48
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Old 2006-08-08, 15:45   #2
Wacky
 
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Do you consider numbers starting with "0" to be properly formed?
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Old 2006-08-08, 16:02   #3
R.D. Silverman
 
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Quote:
Originally Posted by Wacky
Do you consider numbers starting with "0" to be properly formed?
Define 'properly formed'.
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Old 2006-08-08, 16:03   #4
mfgoode
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Wink Elevens!

:surprised
Not really Wacky as it would make a difference in the smallest number if we considered this permissible.
Mally
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Old 2006-08-08, 17:56   #5
xilman
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Quote:
Originally Posted by R.D. Silverman
Define 'properly formed'.
He's asking whether leading zeros are permissible.

Paul
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Old 2006-08-08, 18:28   #6
R.D. Silverman
 
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Quote:
Originally Posted by xilman
He's asking whether leading zeros are permissible.

Paul
I'm sorry. I did not/can not see the original post, so I lost the context.
mfgoode is on my 'ignore' list as I believe that trying to have a
rational discussion with him is pointless.
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Old 2006-08-09, 05:06   #7
mfgoode
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Thumbs down I'm sorry

Quote:
Originally Posted by R.D. Silverman
I'm sorry. I did not/can not see the original post, so I lost the context.
mfgoode is on my 'ignore' list as I believe that trying to have a
rational discussion with him is pointless.
:surprised
Thats okay with me R.D. IT suits me fine. Good riddance to bad rubbish. I dont need you anyway as you seldom solve anything in my opinion. As Dr. Peter would say 'You have reached your level of incompetence' and you intend staying there for quite awhile.
The venom you tend to exude with every post will consume you.
No hard feelings and I wish you luck
Mally
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Old 2006-08-09, 10:13   #8
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102347586
987652413


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Old 2006-08-09, 16:39   #9
mfgoode
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Question Elevens!


You are absolutely right.
Can you give us the rules you used to obtain this ?
Mally
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Old 2006-08-10, 07:13   #10
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Simple:
for the maximum you start with 98765 and then you try to obey to the eleven division rule. Same for finding the minimum, assuming that you cannot put 0 at the beginning, the best you can do is start with 10234

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Old 2006-08-10, 08:14   #11
mfgoode
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Thumbs up Division rules

Quote:
Originally Posted by Kees
Simple:
for the maximum you start with 98765 and then you try to obey to the eleven division rule. Same for finding the minimum, assuming that you cannot put 0 at the beginning, the best you can do is start with 10234


Thank you Kees thats great!

I presume you mean the division rule that if the sum of the digits in the even places is the same as the sum of digits in the odd places then the number is divisible by 11 without a remainder.

However little is known of the the other rule that if the difference between the sum of the odd and the even digits is 11 or a multiple of 11 then it can equally be applied and is valid.

Regards,
Mally
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