Arrange Cows in Pens: 1000 Cows & 10 Pens

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Discussion Overview

The discussion revolves around the problem of arranging 1000 cows into 10 pens such that any number of cows from 1 to 1000 can be obtained by selecting certain pens. The focus includes mathematical reasoning and conceptual exploration of binary representation in this context.

Discussion Character

  • Exploratory, Mathematical reasoning, Conceptual clarification

Main Points Raised

  • One participant suggests that the arrangement of cows can be modeled using binary representation, proposing a specific distribution of cows across the pens: 1, 2, 4, 8, 16, 32, 64, 128, 256, and the remaining 489 cows.
  • The same participant notes that for numbers smaller than 489, the first 9 pens can be opened according to their binary representation, while for larger numbers, the 489 pen must also be included.
  • Another participant questions whether this puzzle has been discussed recently, indicating a potential overlap with previous discussions.
  • A further participant reflects on the historical context of weights and measures, relating the binary arrangement to their experience with weights that could be combined to measure any value, and questions whether the choice of 16 ounces per pound was intentional or coincidental.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the arrangement method, and multiple viewpoints are presented regarding the binary representation and its implications.

Contextual Notes

There are unresolved questions regarding the historical context of weights and measures and whether the binary arrangement is the only viable solution to the problem.

keemosabi
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Given 1000 cows and 10 pens, you want to arrange the cows in the pens such that any number of cows from 1 to 1000 can be obtained by opening certain pens and taking all the cows in those pens. How do you arrange the cows in the pens?
 
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This is equivalent to finding a binary representation for a number. Arrange the cows like this

1, 2, 4, 8, 16, 32, 64, 128, 256 and the remaining 489

If the given number is smaller than 489, then simply open the first 9 pens according to the binary representation of the number. If the number is larger then open the 489 pen, and open the remaining again in binary.
 
Did we just recently have this puzzle?
 
Concerning the solution to the riddle. The use of the binary notation is interesting.When I was younger and we weighed in lbs and ozs we had a set of scales with weights that stacked neatly by the side of the scales The weights were 1,2,4,8 and 1 lb =16oz then the same with lb weights stopping at7lb , I think.
My mother could weigh any weight with these. Question. Was the 16 ounces =One pound deliberately chosen for the given reason or was it accidental??
 

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