Question about some burning rope.

[silverfish]

You are given two ropes of different length and a book of matches. You are told that the ropes, when lit on fire, don’t burn at a consistent uniform rate - within the rope, sometimes they burn fast and sometimes they burn slow and sometimes they burn normally. Also, you are told that each rope will take EXACTLY one hour to burn from one end to the other. You are told that you need to take these two pieces of rope and the book of matches and use them to determine when EXACTLY 45 minutes has elapsed. How would you do it - and the right answer isn't, "I'd look at my watch." You only have the rope and matches.

I don't know the answer.

 

[KillahBee]

I remember this from somewhere.

You burn one of the ropes at both ends and the other at one end - the first rope will take 30 minutes to burn. Then the next rope will have 30 mins left, so you light the other end. Then that burns in 15 mins.

 

[KillahBee]

What's up silverfish, haven't seen you around a lot lately.

 

[silverfish]

Thanks, that's what I found on Google. They're giving away $50 in a drawing with all the correct answers at work.

 

[silverfish]

What's up silverfish, haven't seen you around a lot lately.

I've been here, watching my k disappear in the bookie forum. Otherwise, when I find the time, I'm a lurker.