Jump to content
BrainDen.com - Brain Teasers

gavinksong

Members
  • Content count

    435
  • Joined

  • Last visited

  • Days Won

    9

gavinksong last won the day on April 16 2015

gavinksong had the most liked content!

Community Reputation

11

About gavinksong

  • Rank
    Advanced Member

Profile Fields

  • Gender
    Male
  • Location
    i'm a bird

Recent Profile Visitors

4318 profile views
  1. Balancing Gold Coins

    Congratulations! Unfortunately, the answer changes if I grant you this boon, so request denied. But no worries! You've still solved it. The only thing that changes... And so the answer becomes the one you initially gave. I'd also like to give my own explanation of the recursive step for "constrained" coins. Some may find it interesting and/or more intuitive.
  2. Balancing Gold Coins

    This is actually correct! Another way to write it: However, your rationale has a few loose ends. I am interested in seeing your full solution. Equivalently, what is an explicit algorithm?
  3. I bake

    Wow, I feel pretty stupid. You were literally asking for the three lowest solutions. I don't know what I was thinking.
  4. I bake

    Perhaps... but sometimes there is more than meets the eye, my friend. I shall put forth another guess.
  5. Balancing Gold Coins

    I'm sorry if I wasn't clear. I was asking for an answer in terms of N (number of weighings allowed). After all, the maximum number of coins from which you can pick out the fake is not constant and in fact increases with N. On the other hand, the method you outlined is a reasonable first attempt. You do have one blind spot... It is possible to calculate the maximum number of coins your method could work for (in terms of N). There is a more efficient method that works for larger numbers of coins. P. S. It is common to hide any revealing content inside spoilers (like I did above). The "eye" icon on the very left of the toolbar allows you to insert them into your responses.
  6. Count the Flags

  7. Cross Cornering

    Here's what it looks like when I solve for the error. Unless I've made a mistake?
  8. Cross Cornering

    Oh, I see. That makes more sense. In that case, there's one equation that pops into my head. Seems a bit messy.
  9. Cross Cornering

    I thought we needed to calculate how far we needed to move the corner that was off? Is it unnecessary to use the fact that one of the diagonals is 6 cm longer than the other?
  10. Count the Flags

    Hmm. Since distances aren't bounded, we can't store them in memory. You could mean... Also, On further reflection, it appears that you are right.
  11. Balancing Gold Coins

    Actually, I just did the math...
  12. Balancing Gold Coins

    I will confirm that it is possible even when it is not known whether the fake is lighter or heavier. In your first guess, you had a power of two, which makes me think you were inspired by binary search. Remember that a balance scale has three possible outcomes. Even then, the answer is not as simple as 3^n/2.
  13. I bake

    OH, haha. Is one of the answers...
  14. I bake

    Once again, I'm not sure I understood the question correctly (sorry). I think you're asking for three numbers, but I only have one. It's in the spoiler.
  15. Did you get more than me? pt. 2

    Assuming all the men are highly intelligent,
×