Which marble is the oddball? Heavy or light?

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    Weighing
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Discussion Overview

The discussion centers around a classic puzzle involving 12 marbles, where 11 are identical and one is either heavier or lighter. Participants explore the challenge of identifying the odd marble using a balance scale within three weighings. The conversation touches on the puzzle's popularity and participants' experiences with solving it.

Discussion Character

  • Exploratory, Debate/contested, Homework-related

Main Points Raised

  • One participant presents the puzzle, outlining the conditions and constraints of the challenge.
  • Another participant notes the frequent posting of this puzzle in the forum, suggesting its popularity among users.
  • A different participant reflects on their experience with the puzzle, indicating it was a challenging and rewarding problem to solve.
  • Another participant compares this puzzle to another well-known puzzle about crossing a river with cannibals, expressing that they found the marble puzzle more difficult.

Areas of Agreement / Disagreement

Participants express varying levels of difficulty with the puzzle, but there is no consensus on a solution or method to identify the odd marble.

Contextual Notes

Participants reference previous discussions and similar puzzles, indicating a broader context of interest in logic puzzles within the forum.

Who May Find This Useful

Individuals interested in logic puzzles, problem-solving strategies, or those seeking to engage with challenging brain teasers may find this discussion relevant.

Physics-Learner
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i give you 12 marbles. 11 of them are identical. the 12th one looks the same, but is either heavier or lighter than the other 11.

you also have a balance scale. the kind that weighs things on both sides - and if one side is heavier, it tilts down.

you are allowed only 3 weighings.

tell me which ball is the oddball, and whether it is heavy or light.
 
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This was just posted one or two months ago. In fact, a search for "balance" in the Brain Teasers forum shows that it is posted quite frequently. I wonder what it is about this particular puzzle that makes it so popular.
 
sorry about that. i did look thru the first page for marbles, and did not see anything. i didnt look more closely at the rest of the wording.

to answer your question - it took me a long time to figure it out. it has been one of the best puzzles that i have worked on for a long time.
 
i was just about to post the one about crossing the river with cannibals, but i find that this has also been posted. it only took me an hour or so to figure that one out. i found the marble one much more difficult.
 

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