Logic Puzzle: Buying donuts puzzle

re: Logic Puzzle: Buying donuts puzzle

Neil — Tue, 16 Jun 2009 19:33:38 GMT

Hi, I found a website with logic puzles online. It's Crosswords-world.net, and this is the link to nonograms section <a href="http://crosswords-world.net/jap/">японские">http://crosswords-world.net/jap/">японские кроссворды</a> or this http://crosswords-world.net/jap/. There are more interesting puzzles.

re: Logic Puzzle: Buying donuts puzzle

imRahulSoni — Mon, 11 Aug 2008 20:08:00 GMT

That was cool :-)

Thanks for posting it Tom.

re: Logic Puzzle: Buying donuts puzzle

ASP.NET Debugging — Mon, 04 Aug 2008 23:28:22 GMT

The answer is now posted at:

http://blogs.msdn.com/tom/archive/2008/08/04/answer-login-puzzle-buying-donuts-puzzle.aspx

re: Logic Puzzle: Buying donuts puzzle

Douglas Adams — Mon, 04 Aug 2008 23:14:03 GMT

If I where to guess 42. Which is the Answer to Life, the Universe, and Everything.

ANSWER Login Puzzle: Buying donuts puzzle

ASP.NET Debugging — Mon, 04 Aug 2008 20:16:32 GMT

Here is the answer to the question that was posted, here . There are a few ways to answer this, you can

re: Logic Puzzle: Buying donuts puzzle

joshka — Sun, 03 Aug 2008 18:32:34 GMT

ans: 43

1. can buy any amount where n % 3 = 0 for n>=6

as:

9x0 + 6x1 = 6

9x1 + 6x0 = 9

9x0 + 6x2 = 12

9x1 + 6x1 = 15

9x0 + 6x3 = 18

...

2. similarly any amount where n % 3 = 2 for n>= 26

(26 % 3 = 2, and 26= 20+6)

3. similarly any amount where n % 3 = 1 for n >= 46 (20x2 + 6)

thus:

as n % 3 = 0, 1, or 2 for all n, the answer is less than 46.

45 % 3 = 0 (thus from 1, buyable)

44 % 3 = 2 (thus from 2, buyable)

43 % 3 is not buyable

lots missed from this logic for a full proof, but it's close enough.

re: Logic Puzzle: Buying donuts puzzle

Hanan — Sun, 03 Aug 2008 13:12:30 GMT

The answer is 5, you can purchase any number greater than that, it will just require purchasing a few extra donuts along with them.

re: Logic Puzzle: Buying donuts puzzle

Matthew Dennis — Sun, 03 Aug 2008 05:29:02 GMT

37, after that there is a sequence of 6 numbers that can be made, so by adding 6 to the numbers allows the remaining numbers to be made.

Used BFI alogrithm (brute force and ignorance)

re: Logic Puzzle: Buying donuts puzzle

Andrey Andreev — Sat, 02 Aug 2008 01:28:10 GMT

My wife calculated the number 43. She showed 43 to be impossible and the 6 numbers after 43 to be "possible", by which one easily concludes that every larger number is possible (by adding a 6box to a proved one). I can post a detailed proof if requested

re: Logic Puzzle: Buying donuts puzzle

Jean-Philippe Leconte — Fri, 01 Aug 2008 23:42:54 GMT

Answer: 43

Just by listing the possible answers, you find out that the first 6 sequential numbers you can produce are 44 to 49, those allow you to produce all possible numbers.

For fun : 6, 9, 12, 15, 18, 20, 21, 24, 26, 27, 29, 30, 32, 33, 35, 36, 38, 39, 40, 41, 42, 44, 45, 46, 47, 48, 49...

Didn't even have to fire Mathematica... ;) but thx for the puzzle. (yes, I doubled every letter in my email domain part)