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## Question

Lets say there were 4 men who went to a town to buy things for their fishing trip. 2 of them bought oars and two bought roap. on the way home they came across a river. the only way they could cross it is by rowing in a boat. only 2 can go across each time. how can yo0u get all four of them over to the other side

## 28 answers to this question

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Lets say there were 4 men who went to a town to buy things for their fishing trip. 2 of them bought oars and two bought roap. on the way home they came across a river. the only way they could cross it is by rowing in a boat. only 2 can go across each time. how can yo0u get all four of them over to the other side

I don't know if I'm missing something here, but...

Set one as the designated rower, and he can go back and forth taking one at a time until they are all over.

Unless you are looking for something like tie one end of the rope to the boat, send two across, leave the oars in the boat and pull it back with the rope and then send the other two across?

Maybe the question needs some other condition to be stated?

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It seemed really easy, and I'm not sure if i misunderstood it...

2 across, one back, 2 across, one back, rinse and repeat.

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I'm a little confused as to how all the men went to town just fine, but on the way back home somehow encountered a river.

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Wait! maybe there is another condition that he forgot to state, but meant to. Maybe the people can only use what they bought, two can only use oars, and the other two an only use rope... This would make it at least a little more interesting...

And lol Lausus I didn't even think of that!

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Wait! maybe there is another condition that he forgot to state, but meant to. Maybe the people can only use what they bought, two can only use oars, and the other two an only use rope... This would make it at least a little more interesting...

And lol Lausus I didn't even think of that!

I had thought of that, but ...

... then that would only make it more interesting if each oarsmen could only use their own oar. Then, assuming that if only one was in the boat with one oar that it would just go round in circles, both oarsmen would have to be in the boat to row it across. Then, in order to get the other two across you are talking about tying the rope to the boat and then using the rope to pull the boat across. But where do you draw the line - for example, can an oarsmen tie the rope to the other side of the river as long as he doesn't try to pull the boat....?

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I had thought of that, but ...

... then that would only make it more interesting if each oarsmen could only use their own oar. Then, assuming that if only one was in the boat with one oar that it would just go round in circles, both oarsmen would have to be in the boat to row it across. Then, in order to get the other two across you are talking about tying the rope to the boat and then using the rope to pull the boat across. But where do you draw the line - for example, can an oarsmen tie the rope to the other side of the river as long as he doesn't try to pull the boat....?

Well, it is very possible to row a small boat with only one oar, so you wouldn't need two oarmen.

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Well, it is very possible to row a small boat with only one oar, so you wouldn't need two oarmen.

But I doubt he would be able to row very well with someone else in the boat. Maybe if he was by himself, but it would be too crowded with company (at least in the type of boat I'm thinking of)

I wonder... In the original question it states "Two of them bought oars" does this mean two of them bought one oar each? or two of them bought two oars each? More importantly, does it make a difference?

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Lets say there were 4 men who went to a town to buy things for their fishing trip. 2 of them bought oars and two bought roap. on the way home they came across a river. the only way they could cross it is by rowing in a boat. only 2 can go across each time. how can yo0u get all four of them over to the other side

Hmmm, it just became more difficult. We are not told the men actually had a boat, only that one was necessary. They now need to use the (assumed) two oars and rope to build a boat.

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Hmmm, it just became more difficult. We are not told the men actually had a boat, only that one was necessary. They now need to use the (assumed) two oars and rope to build a boat.

And since it never states how many oars or how much rope were purchased, they obviously bought plenty of oars, and rope, and made a boat like you mentioned. Then use the leftover oars to row across in the 2, 1 back, 2, 1 back fashion.

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Or maybe they built two boats and two men lead in one boat with the other two following in their boat.

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and they would need a boat

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and they would need a boat

Check above posts, they "obviously" need to build one since they didn't have one to begin with

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Well, it is very possible to row a small boat with only one oar, so you wouldn't need two oarmen.

But if one person could row with one oar, then we are back to the original answer of him being the designated oarsman and just goes back and forth. That's why I thought we'd have to make the additional assumption of both having to be there at the same time.

This is all getting very confusing. Surely it can't just be about building a boat with oars and rope (which would more likely be a raft)?? There has to be something missing from this question?

Actually - it can't be about building a boat - because there is the condition that only two can go across at once, which must be imposed by the boat, so the boat must already exist. Otherwise they could just build a boat that would take all four of them.

Edited by neida

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D'oh - You guys were oh so close -

The crossed the bridge that they came across to get to town in the first place.

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There's definitely information missing. We are just trying to think critically with what we have. We know the number of men, their supplies, and that the only way across the river is a boat that can carry two men at a time. Therefore, they need a boat if they want to cross. Then again, they want to go fishing right? So maybe they should do that first.

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D'oh - You guys were oh so close -

The crossed the bridge that they came across to get to town in the first place.

Sorry, the original problem says the only way across is with a boat. Maybe they had a boat the first time they came, or they didn't originally come from home. Maybe they came from work to the store and so avoided the river.

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But if one person could row with one oar, then we are back to the original answer of him being the designated oarsman and just goes back and forth. That's why I thought we'd have to make the additional assumption of both having to be there at the same time.

Which is why i suggested that It might be possible to have one person row, but only if he's alone. Conceivably he could switch the oar from side to side of the boat, but if someone was sitting next to him, he wouldn't be able to...

Just a theory

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D'oh - You guys were oh so close -

The crossed the bridge that they came across to get to town in the first place.

Who says they crossed a bridge to get to town? They can only cross by boat like the problem says. Just one possibility:

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I like that you included a forest.

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It seemed really easy, and I'm not sure if i misunderstood it...

2 across, one back, 2 across, one back, rinse and repeat.

Yeah I like rinse, I wasÂ´nt sure if 2 bought rope [roap] or soap. <_<

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Lets say there were 4 men who went to a town to buy things for their fishing trip. 2 of them bought oars and two bought roap. on the way home they came across a river. the only way they could cross it is by rowing in a boat. only 2 can go across each time. how can yo0u get all four of them over to the other side

Well "roap" is a bit confusing , so maybe we should challenge "boat" also.

Anyway if they did use a boat, the quickest way of crossing is for the first 2 to pull the rope with them, and the other 2 pull the boat back.

Edited by jword

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I like that you included a forest.

and the river suddenly disapeared

and besides, there was no rope, only roap (i though at first it was road), no boat is even in the problem, and they had 2 oars and a fishing poll, and you didnt mention another body of water so you dont need a oar to fish, cast from the bank.

kiger

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haha i felt like it needed it

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RIGHT OK!

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AMAZING!! That is just delightful. Wow. Great solution. Great pictures. Very amusing. Unfortunately, the boat is still the only way across.

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