Finding the Heavier Doobie: Determining the Hash-filled One in 2 Weighs

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The discussion revolves around a logic puzzle involving nine doobies, one of which contains hash, making it heavier than the others. The challenge is to identify the heavier doobie using a balance beam scale with only two weighings. The proposed method involves grouping the doobies into sets and comparing their weights in a systematic way. If the first group (1, 2, 3) is the heaviest, further comparisons within that group will identify the heaviest doobie. If the first group is the lightest, the next group (4, 5, 6) is weighed, and similar logic applies. If the first two groups balance, the last group (7, 8, 9) is weighed to find the heavier doobie. The conversation also touches on other mathematical puzzles and includes a light-hearted exchange about the difficulty of math, with one participant expressing frustration over their mathematical abilities.
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There are nine doobies on a table of equal size but one of them contains hash which makes it weigh more than the other eight doobies. You have a balance beam scale in front of you that you can use weigh the doobies only twice. Determine the method of finding out which doobie contains the hash, using only two weighs.
 
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Weigh 123x456 .
If 123 is the heaviest, then weigh 1x2 . If 1 equals 2 , pick 3 ; if not, pick the heaviest.
If 123 is the lightest, then weigh 4x5 . If 4 equals 5 , pick 6 ; if not, pick the heaviest.
If 123 equals 456 , then weigh 7x8 . If 7 equals 8 , pick 9 ; if not, pick the heaviest.

________________

I hope you have understood the Forty 1lb Weights' solution...
 
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BTW, take a look at the threads 'Nine Digit Numbers' and
'I lost my calculator batteries in a flood' , too.

I guess you've lost your calculator batteries... :smile:
 
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Roger that Rogerio. Sorry I am not a math guy. I try and try but ultimately I am stupid. The doctor forgot to catch me when I popped our of my mother and I landed head first. P.S. My lb. weight solution is correct I think, if you can only put weights on one scale end.
 
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