Weighing Trouble: Find the Set with 5kg Balls

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SUMMARY

The discussion revolves around a riddle involving 10 sets of balls, where 9 sets contain balls weighing 10kg each and 1 set contains balls weighing 5kg each. The challenge is to identify the set with the lighter balls using a digital weighing machine only once. The solution involves taking a specific number of balls from each set, weighing them together, and calculating the total weight to determine which set contains the 5kg balls based on the deviation from the expected weight.

PREREQUISITES
  • Understanding of basic arithmetic and weight measurement.
  • Familiarity with digital weighing machines.
  • Knowledge of problem-solving techniques in logic puzzles.
  • Ability to analyze and interpret numerical data.
NEXT STEPS
  • Research strategies for solving logic puzzles and riddles.
  • Explore the principles of weight measurement and calibration of scales.
  • Learn about combinatorial problem-solving techniques.
  • Investigate similar riddles and their solutions for practice.
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This discussion is beneficial for puzzle enthusiasts, educators in mathematics, and anyone interested in enhancing their logical reasoning and problem-solving skills.

ashishsinghal
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suppose you have 10 sets of balls containing 10 balls each. out of these 9 sets have all balls weighing 10kg (individually) and 1 set has 5kg balls. You can use the digital weighing machine once. how will you wind out which set has 5kg balls?
 
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I'd pick 1 ball from the first ball, 2 balls from the next, 3 balls from the next, and so on. Then I'd weigh them, and the result would tell me which balls are lighter.
 
You got it right. Did you think of it or you knew it. Even for the "Two Doors". You seem to be a professional.
 
Well, the two doors was something I knew of before. But I don't think I've solved this one before. It was a fun riddle though :smile:
 

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