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Subject: "1+11+111=1111"     Previous Topic | Next Topic
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Krys
guest
Aug-24-05, 07:40 PM (EST)
 
"1+11+111=1111"
 
   This may seem simple to most of you, but I need to figure this out. How can I solve this equation by moving only one "toothpick" the plus signs count as 2 toothpicks, and I am not allowed to use the =1111 part of the equation. Please help me, I am trying this site for the first time. Thank you. Krys.


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  Subject     Author     Message Date     ID  
1+11+111=1111 Krys Aug-24-05 TOP
  RE: 1+11+111=1111 mpdlc Oct-24-05 1
  RE: 1+11+111=1111 mr_homm Oct-24-05 2
     RE: 1+11+111=1111 Graham C Oct-24-05 3
         RE: 1+11+111=1111 mpdlc Oct-24-05 6
         RE: 1+11+111=1111 mr_homm Oct-24-05 8
  RE: 1+11+111=1111 ramsey2879 Oct-24-05 4
     RE: 1+11+111=1111 mpdlc Oct-24-05 5
     RE: 1+11+111=1111 mr_homm Oct-24-05 7

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mpdlc
guest
Oct-24-05, 06:34 AM (EST)
 
1. "RE: 1+11+111=1111"
In response to message #0
 
   Out of the jocose tentation of getting one of the thoothpick and crossing the equal sign, I think is pretty easy.

Get the one of the thoothpick of 11 on crooss the center thoothpick of 111 you get 1 + 1 + 1 + 1 = 1111. Which the notation for the number 4 in the uncommon base 1.

Of course you can also take one of the toothpick of 111 and pass to the first term getting 11+11+11 = 1111 which will be valid in the extravagant base (2^.5) where 11 means ((2^.5)+1)
and 1111 = (2+ (2^1.5)+ (2^.5)+1 ) = 3((2^.5)+1), balancing the equation

There more base where the equation could be solved but base it will even more extravagant.

There are several pages in this website covering the numeration base suject, I suggest you take a look of them.

https://www.cut-the-knot.org/recurrence/conversion.shtml


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mr_homm
Member since May-22-05
Oct-24-05, 09:55 AM (EST)
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2. "RE: 1+11+111=1111"
In response to message #0
 
   It is also possible to look at them as Roman numerals. Remove the vertical toothpick from the second "+" sign, and attach it to the first toothpick of "11" to form "VI" (|/ makes V). Then the equation gives | + |/ | - ||| = ||||, so 1 + 6 - 3 = 4.

This problem is interesting because since you only see "|"s, the mathematical base could be anything, such as base 2^5 or base 1 or Roman. I think the "|" symbol was even used in ancient Babylonian numbers (it is a very common symbol, and it means "one" for almost every culture), so perhaps there is another Babylonian solution also. I do not know the details of their number writing system, so I can't say for sure.

--Stuart Anderson


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Graham C
Member since Feb-5-03
Oct-24-05, 03:54 PM (EST)
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3. "RE: 1+11+111=1111"
In response to message #2
 
   >
>This problem is interesting because since you only see "|"s,
>the mathematical base could be anything, such as base 2^5 or
>base 1 or Roman.
>--Stuart Anderson

I'm a little put out by the concept of 1111 in base 1. In base 10 you can use the digits 0-9, in base 3 0-2 and so on. Logically that should lead to only using the digit zero in base 1. If you're going to allow 1, then why stop there? Why not write 2323 for 3*1^0 plus 2*1^2 plus 3*1^3 plus 2*1^4 = 1111111111 (or 10 decimal)?


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mpdlc
guest
Oct-24-05, 09:58 PM (EST)
 
6. "RE: 1+11+111=1111"
In response to message #3
 
   You are partially right the monary system only have one symbol and this is 1 not the 0.

In the monary numeration system the zero is just a non existing entity, it was an empty space. There is evidence that primitive cavemen carved in a stickbones grooves to tally their hunting pieces. They leaved an empty space probably for the no hunting period and started to carve again.

The zero was a creation of the Babylonian, they used just as a placeholder, otherwise without it their numeration system based on position could produce different numbers, so YY could mean 60 or 3601 so they decided to write YY for 60 and Y#Y for 3601 with the spaceholder # (obviously my keyboard has not same symbols the babylonian used Y for 60 or # for the zero).

But unfortunally the zero got lost in the Western Civilization, until was introduced by Fibonacci in the thirteen century, and it took almost two centuries to get accepted.

Romans or Greeks numerals had no symbol for zero,they did not need a placeholder. So they start to count the calendar with year one, that is why we got into the discussion if 2000 or 2001 was the first year of the twenty one century.

Probably you can get more accurate information but that is what I remember.



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mr_homm
Member since May-22-05
Oct-24-05, 10:09 PM (EST)
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8. "RE: 1+11+111=1111"
In response to message #3
 
   >
>I'm a little put out by the concept of 1111 in base 1. In
>base 10 you can use the digits 0-9, in base 3 0-2 and so on.
>Logically that should lead to only using the digit zero in
>base 1. If you're going to allow 1, then why stop there? Why
>not write 2323 for 3*1^0 plus 2*1^2 plus 3*1^3 plus 2*1^4 =
>1111111111 (or 10 decimal)?

Yes, I've always been a bit bothered by that. It'seems to me that you can't extend the standard interpretation of base n notation to the case n=1. You should only be allowed one digit'symbol, and it should be 0, but in that case, the only number you can represent is 0 itself, since, for instance,000 = 0*1^2 + 0*1^1 + 0*1^0 = 0+0+0 = 0.

On the other hand, using 1 as the digit does provide a unique string of digits to name any positive integer, so this version of base 1 does function as a numeration system. I see two possibilities here: first, there may be some non-standard way of looking at positional notation that agrees with the standard way for n>1 and also works for the n=1 case. If so, I don't know what it might be -- perhaps it is an interesting puzzle.

Second, perhaps one shouldn't look at these strings of "1"s as a base system at all. After all, since 1^n = 1, all the positions have equivalent values, so that it isn't really "positional" after all, since the position of a digit has no bearing on its value. Instead, it is a primitive counting notation where the symbols are in direct one to one correspondence with the items counted, like cutting notches in a stick, or using hashmarks to keep a tally.

I think that's it -- base 1 is really just hashmarks, which happen to look like the numeral "1" (which probably started out as just a hashmark itself, so it's no coincidence), and therefore got to be called "base 1" but are really not related to the base n positional system at all.

--Stuart Anderson


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ramsey2879
guest
Oct-24-05, 05:56 PM (EST)
 
4. "RE: 1+11+111=1111"
In response to message #0
 
   No need to mess with the plus signs if you work in base 1 since you only need to take one of the toothpicks from the 2 or 3 and move to the right hand side of the equation since 1 and 2 and 2 = 5 or since 1 and 1 and 3 = 5.


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mpdlc
guest
Oct-24-05, 09:01 PM (EST)
 
5. "RE: 1+11+111=1111"
In response to message #4
 
   I believe the problem posted states you are not allow to touch the second member of the equation. Furthermore I got the clue to resort to the plus sign when it is said is made by using two toothpicks. This last assertion would be unnecesary otherwise.

First I try to solve without move anything so I set

(B^0)+(B^1+B^0)+(B^2+B^1+B^0) = (B^3+B^2+B^1+B^0) or simplifying:

B^3+B^2-B^1=2 is a cubic without an inmmediate solution, so I realize you must swicth some 1 and mess with the sign to get a more easy root for B the unknown base.

The easiest but not the only one I found is:

(B^0)+(B^0)+(B^0)+(B^0)= (B^3+B^2+B^1+B^0)

what yield B=1. 0r 1+1+1+1 = 4.


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mr_homm
Member since May-22-05
Oct-24-05, 09:58 PM (EST)
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7. "RE: 1+11+111=1111"
In response to message #4
 
   >No need to mess with the plus signs if you work in base 1
>since you only need to take one of the toothpicks from the 2
>or 3 and move to the right hand side of the equation since 1
>and 2 and 2 = 5 or since 1 and 1 and 3 = 5.

I believe the original post said that you could not change the right side of the equation.

--Stuart Anderson


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