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09-28-2012, 08:34 AM   #9361
Iznogood
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Quote:
 Originally Posted by Stitchawl Only in math problems can you buy 60 cantaloupes and nobody asks what the hell is wrong with you... Stitchawl
What's wrong with 60 cantaloupes? I have once bought pi fourths of a circle to build my new house upon... maximizing the size of the property vs. the cost

I'll be back with a question as soon as I can think of one

Last edited by Iznogood; 09-28-2012 at 09:02 AM.

 09-28-2012, 01:37 PM #9362 Iznogood Guru     Posts: 929 Karma: 15752887 Join Date: Mar 2011 Location: Norway Device: Ipad, kindle paperwhite All right. Then I have a question. And guess what - there's math involved here also. But it's not advanced math, rest assured... Here goes: A bridge will collapse in 17 minutes. 4 people want to cross it before it will collapse. It is a dark night and there is only one torch between them. Only two people can cross at a time. Person A takes a minute to cross. Person B takes 2 minutes to cross. Person C takes 5 minutes to cross. Person D takes 10 minutes to cross. How do they all cross before the bridge collapses? Bonus question: It was very late yesterday night I worked on Fbones question, and I made a big mistake. A mistake so big I had foul nightmares about this all night. In my answer I listed all the possible combinations of integers whose product was 72, or at least I thought I did. But after thinking about it, I now see I missed 50% (sic(k)!) of the possible combinations. Who can find the missing possible ages of the children?
09-28-2012, 02:05 PM   #9363
Billi
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Quote:
 Originally Posted by norway1456 But after thinking about it, I now see I missed 50% (sic(k)!) of the possible combinations. Who can find the missing possible ages of the children?
You've missed the "1" as in 1 * 6 * 12 or 1 * 8 * 9 (I refuse to regard 1 * 2 * 36 or 1 * 1 * 72 as possible answers )

09-28-2012, 02:20 PM   #9364
Iznogood
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Quote:
 Originally Posted by Billi You've missed the "1" as in 1 * 6 * 12 or 1 * 8 * 9 (I refuse to regard 1 * 2 * 36 or 1 * 1 * 72 as possible answers )
Yes, I missed the "1" when I factorized. Please don't tell my professor

1 1 72
1 2 36
1 6 12
1 8 9

are possible solutions, although the two first are a bit farfetched, as you say. There are still two possibilities not mentioned yet in the thread. THere should be a total of six combinations of ages containing a one-year-old

 09-28-2012, 03:12 PM #9365 Billi Wizard     Posts: 3,374 Karma: 14052629 Join Date: Jun 2009 Location: Berlin Device: Cybook, iRex, PB, Onyx Then 1 * 3 * 24 and 1 * 4 * 18 have not been mentioned yet, with the same caveats and I don't know if they count as children for the census.
09-28-2012, 03:13 PM   #9366
pdurrant
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Quote:
 Originally Posted by norway1456 Yes, I missed the "1" when I factorized. Please don't tell my professor 1 1 72 1 2 36 1 6 12 1 8 9 are possible solutions, although the two first are a bit farfetched, as you say. There are still two possibilities not mentioned yet in the thread. THere should be a total of six combinations of ages containing a one-year-old
1 3 24
1 4 18

09-28-2012, 03:21 PM   #9367
pdurrant
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Quote:
 Originally Posted by norway1456 Here goes: A bridge will collapse in 17 minutes. 4 people want to cross it before it will collapse. It is a dark night and there is only one torch between them. Only two people can cross at a time. Person A takes a minute to cross. Person B takes 2 minutes to cross. Person C takes 5 minutes to cross. Person D takes 10 minutes to cross. How do they all cross before the bridge collapses?

A&B cross: 2 min
A comes back : 1 min
C&D cross: 10 min
B comes back: 2 min
A&B cross: 2 min

Total time: 17 mins.

The way to work it out is this. There must be three crossings and two crossings back. One of the crossings must take ten minutes. The two crossings back must take at least two minutes in total. That only leaves a maximum of five minutes for the remaining two crossings. If C is doing one of those crossings, that leaves no time for the final crossing.

Therefore, C&D must cross at the same time. But neither can come back, as that would use up more than the time available.

So, neither C nor D can do the first crossing, so A&B must, and one of them must come back. Then, since C&D must cross together, they must do the next crossing, and the other one on the far side must come back. And then A&B cross together again. Either A comes back first and B comes back second or vice-versa. It makes no difference to the overall timing.

 09-28-2012, 03:34 PM #9368 Iznogood Guru     Posts: 929 Karma: 15752887 Join Date: Mar 2011 Location: Norway Device: Ipad, kindle paperwhite Billi correctly found the six remaining solutions to the possible ages of the children (even though, "children" might not be the correct term of all possible solutions), and the Grand Mouse quite correctly managed to rescue all the four people over the falling bridge. Well done and over to you, pdurrant
 09-28-2012, 04:38 PM #9369 pdurrant The Grand Mouse 高貴的老鼠     Posts: 46,977 Karma: 160879481 Join Date: Jul 2007 Location: Norfolk, England Device: Kindle Voyage Name the pet(s) of these cartoon families: The Simpsons The Flintstones The Jetsons The Griffins The Hills The Addams The Pickles
09-28-2012, 04:43 PM   #9370
Bilbo1967
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Quote:
 Originally Posted by pdurrant Name the pet(s) of these cartoon families: The Simpsons The Flintstones The Jetsons The Griffins The Hills The Addams The Pickles
Right, so if we take the 'pet' to be x and assume that x trends towards theta, then y must be the binomial of the square of the number of families. Add that to the 60 canteloupes that Stitchawl mentioned and we get;

The Simpsons - Santa's Little Helper
The Flintstones - Dino
The Jetsons - Astro

09-28-2012, 04:57 PM   #9371
Iznogood
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Quote:
 Originally Posted by Bilbo1967 and assume that x trends towards theta
This assumption is only correct when family sanity of x' family trends towards zero or family insanity (the inverse of family sanity) trends towards infinity

The Griffins' dog is called Brian

Last edited by Iznogood; 09-28-2012 at 04:59 PM.

09-28-2012, 06:13 PM   #9372
pdurrant
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Quote:
 Originally Posted by Bilbo1967 The Simpsons - Santa's Little Helper The Flintstones - Dino The Jetsons - Astro
All correct. But Santa's Little Helper isn't the Simpsons' only pet.

09-28-2012, 06:14 PM   #9373
pdurrant
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Quote:
 Originally Posted by norway1456 The Griffins' dog is called Brian
Correct.

 09-28-2012, 06:18 PM #9374 pdurrant The Grand Mouse 高貴的老鼠     Posts: 46,977 Karma: 160879481 Join Date: Jul 2007 Location: Norfolk, England Device: Kindle Voyage Name the pet(s) of these cartoon families: The Simpsons(1) Santa's Little Helper Bilbo1967 (2) Snowball Bilbo 1967 The Flintstones Dino Bilbo1967 The Jetsons Astro Bilbo1967 The Griffins Brian norway1456 The Hills The Addams The Pickles Bold families have all the pets named (in my opinion). 4 points to Bilbo1967 1 point to norway 1456 It's still anyone's game, with many more than four points left. Last edited by pdurrant; 09-29-2012 at 04:59 AM.
 09-28-2012, 06:30 PM #9375 Bilbo1967 Not scared!     Posts: 10,469 Karma: 49003755 Join Date: Mar 2009 Location: Midlands, UK Device: Sony 600, Sony 650, Sony T2, Xoom, Nexus 7 (2012 & 2013), Nook ST (x2) Is the Simpsons' cat called Snowball?