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Bears and Ferries, Oh My! (July '23 Challenge Question)

Posted June 30, 2023 12:00 AM
Pathfinder Tags: challenge question

There are three men and three bears on the west side of a river. All men and bears must get to the east side of the river using a small paddle boat that can only hold two of them, regardless of species.

The bears will attack if at any point the number of bears outnumber the men on either side of the river or in the boat.

How do the men transport bears -- and themselves - safely across?

ANSWER (07.24.23)

One purposefully unmentioned, yet logical detail is that the bears cannot row themselves across.

@Alex. Roman in comment #4 got it first.

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#1

Re: Bears and Ferries, Oh My! (July '23 Challenge Question)

06/30/2023 3:00 AM

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#2
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Re: Bears and Ferries, Oh My! (July '23 Challenge Question)

06/30/2023 4:07 AM

GA

You've left a man out of the picture on the west/left bank in rows 5 and 6.

This would be better with bishops and actresses: I don't think you can realistically expect the bears to be able to paddle, understand the instructions and comply.

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Re: Bears and Ferries, Oh My! (July '23 Challenge Question)

06/30/2023 5:03 AM

Ha ha yeah..Like the bears need to outnumber the men to attack...I think one would be enough...

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#4

Re: Bears and Ferries, Oh My! (July '23 Challenge Question)

07/02/2023 4:28 AM

This is the solution that doesn't put bears to paddle (I used Solar Eagle's graphic):

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#5
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Re: Bears and Ferries, Oh My! (July '23 Challenge Question)

07/02/2023 12:39 PM

I do believe this is the answer intended by the poser but it does assume that when a man and a bear reach the shore with a solitary bear the man is safe from the two bears. If that assumption is not true then no solution exists unless bears can paddle the boat.

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Re: Bears and Ferries, Oh My! (July '23 Challenge Question)

07/03/2023 2:07 AM

If the man remains on the boat and only the bear gets off, the man is safe. There are also other similar situations that imply that there are simultaneous get on/get off events to keep the man/men safe but there is no restriction to do that.

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Re: Bears and Ferries, Oh My! (July '23 Challenge Question)

07/11/2023 10:08 AM

Due to the existing statement: "The bears will attack if at any point the number of bears outnumber the men on either side of the river or in the boat", the man remains safe if the bear gets off the boat but the man remains on it. There are also other "critical" moments: for example when two men in the boat reach the shore where there are two bears, they must get off simultaneously from the boat, then one bear gets on the boat, followed by one man.

However, if the boat "can only hold two of them, regardless of species" I wonder how can the bears outnumber the men in the boat?

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Re: Bears and Ferries, Oh My! (July '23 Challenge Question)

07/24/2023 4:06 PM

This is the correct answer! Well done.

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#7

Re: Bears and Ferries, Oh My! (July '23 Challenge Question)

07/11/2023 9:34 AM

The question does not specify the type of technology available to the men, so I will presume they have guns and ammo appropriate for bear hunting.

Being practical men they shoot all 3 bears, skin their hides and remove the gall bladders($10000 in Korea) for sale and put everything in the boat and leave.

Come back in a motor boat and get the last guy---maybe...

Nature is not fair, especially not human nature. Big fish eat little fish, etc.

The bears were stupid for just standing there, knowing they are strong swimmers, and could have eaten the men, and swam across the river with the men in their stomachs.

This is survival of the smartest in action.

I would not do that ,just saying someone probably would.(Perhaps oil company executives?)

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