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Guest Message by DevFuse


Member Since 02 Feb 2013
Offline Last Active Jun 21 2014 02:05 AM

Topics I've Started

Halloween Candy

19 November 2013 - 11:52 PM

At a Halloween party, three boxes of candy were set out. Each contained 100 candies, individually wrapped in plain black wrapper. One box contained only chocolate candies, another contained only licorice candies, and the remaining box contained a blend (of unknown proportion) of chocolate and licorice candies. All three boxes were labeled, however, some prankster came by and swapped the labels on two of the boxes.


How many candies would you have to sample in order to set the labels right again?

Weighing Champ

23 October 2013 - 12:08 AM

With a tip of the hat to wolfgang...


Lake Champlain has long been surrounded by rumors of a mysterious creature akin to the Loch Ness Monster. The locals call him "Champ," and he is officially a protected species in both Vermont and New York State. 


And after so many decades of stories and speculation, Champ has been spotted!! Scientists, eager to learn as much as possible about the potentially prehistoric lake monster before he disappears again, have quickly assembled all of the maritime and scientific equipment that they might possibly need. However, owing to Champ's thoroughly protected status, officials have mandated that no experiment shall be conducted which might pose an immediate risk to Champ's life or health; in particular, they stipulate that Champ can not be removed from the lake at any time, even momentarily (nor can the ecosystem of the lake be impacted such as by draining the lake).



Can you find a method to determine Champ's inherent buoyancy?


Can you find a method to determine how much Champ would weigh if he were allowed to be hoisted out of the water and placed on a scale?


The Fork

29 March 2013 - 03:30 AM

With a tip of the hat to itsmeee's 999 puzzle, and bonanvoa's Mad Hatter puzzle...


You come to a three-way fork in the road. You know that one path leads to your destination, and that the other two paths lead to Certain Doom™. You know that in the area is a tribe of truth-tellers and a tribe of liars, both of which will answer appropriately whenever they can, or remain silent whenever they cannot answer a question truthfully (or falsely). A tribesman from one of these tribes -- you know not which -- is standing at the fork, and -- as if for his own amusement -- offers to answer one single question with "Yes" or "No" to help you find your way. What question do you ask him?

The River

25 February 2013 - 01:37 AM

This one isn't too hard, but is a fun exercise. :)


Two motor boats began speeding toward one another at the same time from opposite shores of a river. Upon reaching the opposing shore, each motor boat immediately reversed course and headed back to his original shore. In so doing, the motor boats passed each other twice. The first time they crossed, they were 700 feet from one shore of the river; the second time, they were 300 feet from the opposite shore. Assuming each boat traveled with constant speed, and neglecting any influence of river current, how wide is the river?

Numbered Foreheads Concluded

20 February 2013 - 04:03 AM

Although I believe the logic to answer the original problem was present, it was distributed among several postings... It did not seem right to mark any single post as the best answer. Therefore, here is the bonus round. :)


If approached correctly, this version is not much harder than the original.


The puzzle:


Three perfect logicians had stickers placed on their foreheads so that none could see their own sticker but each could see one another's. They were told that each sticker has a single positive integer written on it (i.e.1, 2, 3, ...), and that the sum of the integers on all three stickers is either 1002 or 1003. They were then asked, in turn, to identify the number on their own sticker. Upon being asked, each logician would name their number if they were sure that they knew it, give up if they were sure that they would never know it, or otherwise 'pass' (or say "I don't know"). The question was repeated, again in turn, until EACH of the three logicians had either named their number or given up. All three stickers actually had the same number written on them. Who among the three logicians was able to deduce his number, and who among them gave up? (Furthermore, how did each answer?)