Can You Solve the Bridge Troll Puzzle?

In summary, the brain teaser is about a very long bridge with a troll in the middle that sleeps for three minutes and wakes up for three minutes. The troll will send anyone on the bridge back to the side they came from. The challenge is to cross the bridge in exactly three minutes and one second. Some suggestions include walking to the troll and then turning back, hiding from the troll's view, or knocking the troll out. However, the correct answer is to start crossing the bridge one second before the troll falls asleep, giving enough time to cross before the troll wakes up. The original source of the riddle is unclear, but the answer provided by Abyss is correct.
  • #1
john1108
1
0
Here is a puzzle that a camp counselor asked me. But unfortunately he forgot to tell me the answer as he said he would at the end of the camp. I checked online at lots of sites but none had this brain teaser. So i hope one of you guys can pm me the answer. Here is the brain teaser.

There is a very long bridge that you have to cross. But, in the middle of the bridge is a Troll. The troll sleeps every three minutes for three minutes(He wakes up three minutes after he sleeps). When he is awake he can see anyone on the bridge. If he sees you on the bridge he will send you back to the original side you came from. If it takes you exactly three minutes and one second to cross the bridge(always, no matter what speed you travel), how do you cross the bridge?
 
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  • #2
Stand on his head?
 
  • #3
I think the answer isn't physics based, but simply clever.

The troll always sends people back to the side they were coming from.

So what you do, is you walk all the way to the beast (50% of the way), then you turn around and walk back (maybe a little slowly), that way when he wakes up, he'll think you came from the other way, and put you on the side you want to be on.
 
  • #4
I thought of that but it does say "back to the original side you came from", which in my books, explictly rules out your solution.
 
  • #5
aha,

but he heard it from a camp counselor, who either read it or heard it somewhere else.

That means that either the counselor told him wrong. He forgot the exact wording, or he wrote it here wrong.

Because my explanation HAS to be right, and you are correct that with that wording it couldn't be (which I thought of too).
 
  • #6
haha well this trick question is really funny and challenging. i have a felling thay abyss is right though
and maybe not too. it has something to do with the 3mins invertions of sleep and the awake of the troll.
 
  • #7
thinking about it, i guess abyss is right from the start, there is no other ways i can think of
 
  • #8
Abyss said:
aha,

but he heard it from a camp counselor, who either read it or heard it somewhere else.

That means that either the counselor told him wrong. He forgot the exact wording, or he wrote it here wrong.

Because my explanation HAS to be right, and you are correct that with that wording it couldn't be (which I thought of too).

It occurred to me too that the telling is now second-hand, which means your answer could be right.

But when it comes to riddles, I don't grant that just because someone only came up with one answer, it's the only one.
 
  • #9
That also occurred to me, but I am absolutely certain that my answer is right, therefore I felt it was unnecessary to say.

Also, kaisxuans's got my back.
 
  • #10
I say knock the troll out and take your time.

But seriously, I think Abyss' answer has to be right.
 
  • #11
if you are an able bodied person, you can hang off the side of the bridge every time before he wakes up.

if the troll is stupid enough, you can bring something to shield yourself from his view, like a piece of cardboard or something.
 
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  • #12
you could start crossing the bridge one second before he falls asleep.. cause he has to fall asleep for 3 minutes.. so in rebuttle that'd allow you with 3 minutes to cross the bridge. but it seems to simple to be a right answer
 
  • #13
both remnant and abyss answers are logical. but remnant, if the troll sees u, you will still get caught. but for abyss, the troll may help him. all in all, it will have to depend on john1108 to tell us if he heared the question right. if it is right, then remnant answer may be right. if not, it is abyss.
(visit my blog!)
 
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  • #14
I've heard this riddle before and the answer that Abyss stated is correct.
 
  • #15
so it is Abyss answer! so john1108 heared it right!
 

1. Can you explain the bridge troll puzzle?

The bridge troll puzzle is a classic logic problem that involves a troll guarding a bridge and three travelers trying to cross it. The puzzle requires critical thinking and problem-solving skills to figure out the most efficient way for all three travelers to cross without getting eaten by the troll.

2. How do you solve the bridge troll puzzle?

The key to solving the bridge troll puzzle is to understand the rules and limitations of the puzzle. The travelers can only cross one at a time and the troll will not allow two travelers to cross at the same time. The solution involves strategic backtracking and choosing the right order for the travelers to cross.

3. What is the significance of the bridge troll puzzle?

The bridge troll puzzle is often used as a brain teaser or a warm-up exercise for problem-solving skills. It also highlights the importance of logical thinking and the ability to think outside the box.

4. Are there different variations of the bridge troll puzzle?

Yes, there are many variations of the bridge troll puzzle, each with its own set of rules and limitations. Some puzzles may have more travelers or a different number of bridge crossings required. This allows for different levels of difficulty and keeps the puzzle interesting and challenging.

5. What are the benefits of solving the bridge troll puzzle?

Solving the bridge troll puzzle can improve critical thinking, problem-solving, and decision-making skills. It also promotes patience, perseverance, and the ability to think ahead and anticipate potential obstacles. These skills are essential in various fields, including science, engineering, and mathematics.

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