apeman5291 wrote:the first puzzle is kind of like this one:

http://math.cofc.edu/MATHMEET/truth-sprint.pdf

What tools were you allowed to use? I'll admit to using a list of the primes and a prime factor program.

**Spoiler:**

- Wed Jun 20, 2007 3:50 pm UTC
- Forum: Logic Puzzles
- Topic: I dare you to solve this.
- Replies:
**82** - Views:
**36131**

apeman5291 wrote:the first puzzle is kind of like this one:

http://math.cofc.edu/MATHMEET/truth-sprint.pdf

What tools were you allowed to use? I'll admit to using a list of the primes and a prime factor program.

- Wed Jun 20, 2007 3:33 pm UTC
- Forum: Mathematics
- Topic: What's your random number?
- Replies:
**92** - Views:
**22737**

- Tue Jun 19, 2007 2:51 pm UTC
- Forum: Logic Puzzles
- Topic: Lock Box solution
- Replies:
**29** - Views:
**7620**

Romeo and Juliet live on opposite sides of a war torn country. Romeo wants to send Juliet a ring. Unfortunately the mail is very corrupt and anything that is sent in the mail that is not in a locked box will be stolen. Both Romeo and Juliet have plenty of boxes and plenty of locks but no keys to ea...

- Mon Jun 18, 2007 5:28 pm UTC
- Forum: Mathematics
- Topic: What's your random number?
- Replies:
**92** - Views:
**22737**

- Fri Jun 15, 2007 10:23 pm UTC
- Forum: Mathematics
- Topic: irrational inches
- Replies:
**31** - Views:
**6154**

- Fri Jun 15, 2007 5:41 pm UTC
- Forum: Mathematics
- Topic: irrational inches
- Replies:
**31** - Views:
**6154**

- Thu Jun 14, 2007 7:54 pm UTC
- Forum: Mathematics
- Topic: a number game
- Replies:
**21** - Views:
**4311**

Well, just because some numbers don't can't win of others are picked, doens't necessarily mean there's a best single strategy. This is a bit like the lowest-unique-bid auction puzzle though. A best strategy for one person is the best strategy for everyone since the game is identical for all players...

- Tue Jun 12, 2007 11:24 pm UTC
- Forum: Mathematics
- Topic: Favorite math jokes
- Replies:
**1452** - Views:
**494906**

What do you get when you cross a donkey with an elephant? A: DonkeyElephant sin ? This is a bad first post because 1. It's not in the introduction thread 2. The joke has been done already in this thread (in this page even) 3. You used obnoxiously large font Try again! 4. http://albinoblacksheep.com...

- Tue Jun 12, 2007 11:19 pm UTC
- Forum: Science
- Topic: Why cant you go the speed of light with this method...?
- Replies:
**34** - Views:
**9276**

Unless he just means that the fuel ejected by the small rocket will eventually hit the big rocket and push it backwards, which is true. Yes this is what I mean. 2 cases: 1) There is an atmosphere inside the mother rocket. The force of the mother rocket is applied by way of the atmosphere (mother ro...

- Tue Jun 12, 2007 6:42 pm UTC
- Forum: Mathematics
- Topic: What's your random number?
- Replies:
**92** - Views:
**22737**

- Tue Jun 12, 2007 6:10 pm UTC
- Forum: Mathematics
- Topic: Epsilon-Delta definition of limits.
- Replies:
**23** - Views:
**7197**

- Tue Jun 12, 2007 5:18 pm UTC
- Forum: Science
- Topic: Why cant you go the speed of light with this method...?
- Replies:
**34** - Views:
**9276**

Relativisitic effects aside, there's also a major flaw with this plan. Things accelerate by pushing off of other things and repelling them in the opposite direction (conservation of momentum). In the rocket's case, it is pushing off of fuel. If a large rocket were carrying a smaller rocket and the s...

- Tue Jun 12, 2007 4:49 pm UTC
- Forum: Mathematics
- Topic: Epsilon-Delta definition of limits.
- Replies:
**23** - Views:
**7197**

A minor detour. Well a large one, but the other day I was thinking about proving algebra of continous functions, particularly for multiplication of continous functions. I managed to come up with a scrappy proof which you had to set a delta to be a certain value if epsillon was less than 1, and diff...

- Mon Jun 11, 2007 7:52 pm UTC
- Forum: Computer Science
- Topic: unary
- Replies:
**4** - Views:
**3772**

- Mon Jun 11, 2007 7:09 pm UTC
- Forum: Computer Science
- Topic: unary
- Replies:
**4** - Views:
**3772**

In a book I am reading it uses the symbols 0 and 1 (in other words 2 symbols) as the simplest set of symbols that can be used to construct a turing machine. But really, couldn't you do it with just one symbol? I'm thinking along the lines of the way the natural numbers can be described by the succes...

- Thu Jun 07, 2007 2:41 am UTC
- Forum: Mathematics
- Topic: 0!=1
- Replies:
**60** - Views:
**11761**

This is really just a rewording of some posts but sometimes phraseology can make all the difference, if the factorial function describes the number of arrangements of n elements, there is only one way you can arrange zero elements. Nah, that phraseology sucks, because one might be inclined to say t...

- Thu Jun 07, 2007 2:32 am UTC
- Forum: Mathematics
- Topic: Math Books
- Replies:
**42** - Views:
**10463**

- Tue May 29, 2007 7:23 pm UTC
- Forum: Mathematics
- Topic: A matter of probability
- Replies:
**13** - Views:
**3432**

- Tue May 29, 2007 4:40 pm UTC
- Forum: Mathematics
- Topic: Find the error (because I sure can't)
- Replies:
**10** - Views:
**4182**

- Tue May 29, 2007 3:55 pm UTC
- Forum: Mathematics
- Topic: Division by Zero (Please, no new threads about this)
- Replies:
**367** - Views:
**85499**

- Sat May 12, 2007 1:41 am UTC
- Forum: Logic Puzzles
- Topic: Hello. [NUMEROLOGICAL PUZZLE, NOT SPAM - LE4dGOLEM)
- Replies:
**18** - Views:
**4373**

- Wed May 09, 2007 4:51 pm UTC
- Forum: Mathematics
- Topic: 1-2+3-4... = -1/4
- Replies:
**22** - Views:
**8426**

Does anyone know of a proof that 1 - 2 + 3 - 4 + . . . still converges to 1/4 (in the Cesaro sense) even if you rearrange the terms? Cesaro sums don't necessarily obey the same rules of addition that we are used to. For example, associativity: (1 - 2) + (3 - 4) + (5 - 6) + . . . = -1 + -1 + -1 + . ...

- Tue May 08, 2007 10:35 pm UTC
- Forum: Mathematics
- Topic: 1-2+3-4... = -1/4
- Replies:
**22** - Views:
**8426**

Also, I know that non-absolutely convergent series can be rearranged so as to equal any value you wish. Does this have anything to do with 1 - 2 + 3 - 4 + ...? The result you are referring to requires a series which is already known to converge, but not to absolutely converge. So that result cannot...

- Tue May 08, 2007 5:55 pm UTC
- Forum: Mathematics
- Topic: 1-2+3-4... = -1/4
- Replies:
**22** - Views:
**8426**

To show that the sum equals 1/4, they start out assuming that s = 1 - 2 + 3 - 4 + ... exists. Since it doesn't, their manipulations don't seem to be valid. I mean you could say: Let x be infinity infinity plus anything is just infinity x + 3 is infinity x + 9 is infinity x + 3 = x + 9 3 = 9 or somet...

- Wed May 02, 2007 5:40 pm UTC
- Forum: Mathematics
- Topic: How many digits of e do you know?
- Replies:
**43** - Views:
**13924**

- Tue May 01, 2007 2:15 am UTC
- Forum: General
- Topic: Marital Arts
- Replies:
**207** - Views:
**31522**

- Fri Apr 27, 2007 5:48 pm UTC
- Forum: Logic Puzzles
- Topic: A field of theorems
- Replies:
**12** - Views:
**3191**

I read it as: T is the set of all theorems that can be derived from the set of axioms that define a field (so, presumably, ZF + field axioms or something?). Find a field structure on T. That is, some theorem should correspond to 0 in the field, some theorem to 1. There should be two binary operatio...

- Fri Apr 27, 2007 12:17 am UTC
- Forum: Logic Puzzles
- Topic: Cliffjumper.
- Replies:
**8** - Views:
**3029**

Also it depends on if by jumping off you mean walking off, or if you actually mean taking a big jump up into the air as you go over the cliff. Although now that I think about it, this probably doesn't make a huge difference. I doubt the differences in atmosphere resistance count for very much over s...

- Thu Apr 26, 2007 11:06 pm UTC
- Forum: Logic Puzzles
- Topic: A field of theorems
- Replies:
**12** - Views:
**3191**

This puzzle is to form a field structure over the set T, which will be defined shortly. It will be necessary to define the operators + and * as well as the identity and zero elements. T is the set of all theorems derivable from the axioms that define a field. Let us call A the set of all axioms gove...

- Thu Apr 26, 2007 6:54 pm UTC
- Forum: Logic Puzzles
- Topic: No digit more than once
- Replies:
**19** - Views:
**5261**

- Thu Apr 26, 2007 5:56 pm UTC
- Forum: Logic Puzzles
- Topic: When is it efficient to take a bus?
- Replies:
**34** - Views:
**5823**

- Wed Apr 25, 2007 10:24 pm UTC
- Forum: Logic Puzzles
- Topic: No digit more than once
- Replies:
**19** - Views:
**5261**

- Wed Apr 25, 2007 6:45 pm UTC
- Forum: Logic Puzzles
- Topic: No digit more than once
- Replies:
**19** - Views:
**5261**

- Wed Apr 25, 2007 5:57 pm UTC
- Forum: Mathematics
- Topic: Division by Zero (Please, no new threads about this)
- Replies:
**367** - Views:
**85499**

The way I see that is each block is infinitly large and goes on forever. However you dont have any blocks so you still dont have anything. Or each box contains absolutely nothing and you may have an infinite number of them, but there is still nothing there. But 0/0 is not the total number of blocks...

- Wed Apr 25, 2007 5:50 pm UTC
- Forum: Logic Puzzles
- Topic: When is it efficient to take a bus?
- Replies:
**34** - Views:
**5823**

Pi - From the units, it looks like you calculated the minutes it would take for the bus to overtake you once the bus arrives at the first stop. x is minutes, not miles. So to finish your calculation you must take (x + 7.5 min)*(3mile/60min)*(8block/mile) = 3.5292... blocks As for the real world solu...

- Wed Apr 25, 2007 5:16 pm UTC
- Forum: Logic Puzzles
- Topic: Sudoku Cube
- Replies:
**20** - Views:
**8522**

I was asked to solve one of these by a friend. I solved it by first analyzing the rotations of the numbers and figuring out which possible orientations the faces could be in when solved. When unfolded, the cube I solved would look like this: 152 463 789 436 142 397 971 751 873 615 248 928 695 824 5...

- Tue Apr 24, 2007 8:31 pm UTC
- Forum: Logic Puzzles
- Topic: When is it efficient to take a bus?
- Replies:
**34** - Views:
**5823**

If you didn't know what time it was or the buses were unreliable, you would wait on average 15/2 min. So the time it takes to travel by bus is WAIT TIME + TRAVELING TIME. Let's say m is the number of miles to travel. The time equation in hours by bus is then: B(m) = 7.5/60 + m/20. The equation by f...

- Tue Apr 24, 2007 4:56 pm UTC
- Forum: Logic Puzzles
- Topic: lowest-price auction variant.
- Replies:
**27** - Views:
**4544**

- Tue Apr 24, 2007 1:25 am UTC
- Forum: Logic Puzzles
- Topic: lowest-price auction variant.
- Replies:
**27** - Views:
**4544**

- Tue Apr 24, 2007 12:04 am UTC
- Forum: Logic Puzzles
- Topic: lowest-price auction variant.
- Replies:
**27** - Views:
**4544**