USPuzzles, Round 1!
Greetings to you, all you clever University Scholars types!
As part of our efforts to reinvigorate our web presence and in honor of this year’s symposium theme of Puzzles, I will be posting a series of (what else?) puzzles to the blog over the next few months. For the moment, the intent will be to share and discuss different puzzle types (so feel free to submit your own favorite puzzles). But come the new year, if there’s interest, the puzzling will get competitive. Oh, yes.
For the first puzzle of the series, I want to share (with a certain admission of solipsism) a puzzle type that was one of my first introductions to recreational puzzling. It’s a kind of logic problem.
Five friends (Adam, Beth, Carlos, Dan, and Elise) have gone to the theatre and are waiting in a single line to buy tickets. You know the following:
- 1. Dan is waiting immediately behind Beth.
- 2. Dan got in line sometime before Elise did.
- 3. Adam and Carlos are next to each other in line, arguing.
- 4. Adam is third in the line of five.
From that information, tell me in what order are the five friends standing?
Feel free to use the comments. I will post the answer, as well as my approach to the problem, over the weekend. Happy Puzzling!
-Christopher Williams
Premise four says Adam is number 3, and premise three says I must be next to him, so I’m either 2 or 4. If I’m 2 then by premise one Beth is 4 and Dan is 5. But Dan is ahead of Elise, so that is impossible in a five person line. (Reductio ad absurdum of Carlos being second in line.)
So Carlos must be 4. There are only two slots left together which must go to Beth and Dan by premise one again. This leaves:
Beth = 1
Dan = 2
Adam = 3
Carlos = 4
Elise = 5
From my favorite puzzle website:
You’re playing bridge. Each of four players is dealt 13 cards. You and your partner find that between you you hold all 13 cards of one suit. Is this more or less likely than that the two of you hold no cards of one suit?
A rail one mile long is lying on the ground. If you push its ends closer together by a single foot, so that the distance between them is 5279 feet rather than 5280, how high an arc will the rail make?
Suppose the earth were a perfect sphere and you fitted a belt around its equator.
The belt would be 40 million meters long. If you now increased its length by a mere 5 meters, how high would it ride above the earth’s surface?
http://www.futilitycloset.com/2011/11/26/stormy-weather-2/?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+FutilityCloset+%28Futility+Closet%29&utm_content=Google+Reader