Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Need solution to this puzzle

  1. Jun 14, 2005 #1
    I am sure this one has been done a million times, but I can't figure this out. It about 10 mint producing machine and one of them is defective and produces coins that weigh 10% less than the other 9. You have a scale but you can only use it once and only once, how would you identify the defective machine?
  2. jcsd
  3. Jun 14, 2005 #2


    User Avatar
    Gold Member

    What have you tried?
  4. Jun 14, 2005 #3


    User Avatar
    Gold Member

    Here's a hint: What's 1+2+3?
  5. Jun 14, 2005 #4
    This puzzle has been presented in a slightly different form in the thread entitled: inspector Columbo.
  6. Jun 15, 2005 #5
    I solved another problem of same kind, which says there are 10 groups of 10 balls each and each ball in a group weighs 10gms except one group which has 9 gm balls in it, by an excellent case of coincidence.

    When I was in school I had a grave problem with my third language and only way out for me is to mug up. I often used to forget part of the essays and poems, so my teacher advised me to count numbers to calm down myself and try remembering them. I was totally baffled when the above problem was given to me and started counting numbers. I got that when I reached 10.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?

Similar Discussions: Need solution to this puzzle
  1. Puzzle for you (Replies: 1)

  2. Ippossible puzzle? (Replies: 12)