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18 comments
Anonymous Poster #1

River Crossing

09/08/2012 11:06 AM

Here is a Challenge Question:

I have 9 kids and 2 Scooter. Each scooter can take 2 kids. The game is to be similar to the River Crossing problem.

How many different roles do the kids have to take on to make the problem solvable?

What roles would you suggest and which boundary conditions have to be introduced to make it work?

I was thinking of at least 4 roles, but I am undecided about conditions. What would you suggest: Can the scooter go simultaniously? Or would this be part of the Solution.

I am not after a bijective solution, just something that needs some thinking.

Creative solutions have a chance to be implemented in a 11 year old birthday party!

DAD

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Guru

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#1

Re: River Crossing

09/08/2012 2:00 PM

Who is the boatman, you or one of the children.

If you, you could do the river crossing with three of each, cabbages, rabbits, and foxes.

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Anonymous Poster #1
#13
In reply to #1

Re: River Crossing

09/09/2012 8:45 PM

Boatman is one of the kids. I am short of one "boat" with what you suggest, but it is still not a bad idea.

Thanks

DAD

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Guru
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#2

Re: River Crossing

09/08/2012 4:49 PM

This puzzle is completely ambiguous and unclear. Is that meant to be the real puzzle?

What 4 possible roles could one have? Driver and passenger are about it.

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Anonymous Poster #1
#15
In reply to #2

Re: River Crossing

09/09/2012 9:03 PM

Ok how unlcear is it? I have 9 kids that I want to have play River Crossing. I have 2 vehicles to represent a boat. So how would one go about to assign roles and relations ( who wants to eat who) so it is bit of a challange for the kids to make transport schedule.

I know it is ambigous and there might be only a complicated solution with 9 roles.

OR

there is a slightly easier set up with fewer roles but multiple solutions.

What is the Math behind the River Crossing?

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Guru
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#3

Re: River Crossing

09/08/2012 5:18 PM

You might have more fun adding this to the river cross puzzle.

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Guru

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#4

Re: River Crossing

09/08/2012 8:59 PM

I would get more scooters.....flying scooters...

Now watch some idiot tell me I missed the whole point....(sic)

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#5
In reply to #4

Re: River Crossing

09/08/2012 10:29 PM

Or Ewok speeders from Star Wars III.

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#6
In reply to #5

Re: River Crossing

09/09/2012 12:20 AM

...or possibly a giant robotic spider,,,if I wasn't in any particular hurry...

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Anonymous Poster #1
#16
In reply to #4

Re: River Crossing

09/09/2012 9:03 PM

Then what?

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Guru

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#7

Re: River Crossing

09/09/2012 2:45 AM

Too easy...

With careful packing you could do it in one trip.

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Guru

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#8
In reply to #7

Re: River Crossing

09/09/2012 3:13 AM

Gee - and neither of those motorbikes even had the added seat in front of the handlebars (above the front fender) like I used to see in Taipei! Nor was anyone wearing a sling with a toddler in it (Taipei again, in late 80's or early 90's). Then again, I never saw more than seven to a bike, anyway . . .

Two scooters, and only nine to move? No sweat!

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Guru

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#9
In reply to #8

Re: River Crossing

09/09/2012 3:54 AM

It gets better than that...

Hundred km trip like this is typical.

How else?

Two wheels rule here.

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#10
In reply to #7

Re: River Crossing

09/09/2012 10:08 AM

It's been done....

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#11
In reply to #10

Re: River Crossing

09/09/2012 10:23 AM

This is so big it could be American!

Riding side saddle. Nice. (mostly anyway)

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#12

Re: River Crossing

09/09/2012 2:01 PM

I say toss em all in the river at once! The one who makes it to the other side first is the winner and whom ever else gets there lives to see another day/elimination game!?

Strangely enough I am seen as being very good with kids. (Scary to think what the bad people are like.)

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#14

Re: River Crossing

09/09/2012 8:55 PM
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#17

Re: River Crossing

09/09/2012 11:26 PM

OP: I believe an explanation, or at least a link to an explanation, of the game would be in order.

http://brainden.com/crossing-river.htm

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Anonymous Poster #1
#18
In reply to #17

Re: River Crossing

09/10/2012 1:31 AM

Thanks a lot! This saves the game. All other comments were kind a not what I expected.

I found a few of the web pages already but on this page there is the one "River Crossing Game" which involves 8 persons. This would do with one kid making sure it all works correctly. (Of course have to bribe this one).

Cheers

DAD

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