Wednesday, April 18, 2007

A Logic Puzzle

A man trapped in a dungeon was contacted by a friend who offered to help him escape and said he would return in 45 minutes. The man had been bound with two ropes of equal length that he estimated would each burn non-uniformly for one hour. How did the man, using the ropes and a candle in his cell, count the passing of 45 minutes?

7 comments:

sibbie said...

C'mon, help us out here. I'm stumped.

Vie said...
This comment has been removed by the author.
Cameron said...

my only guess is that it has nothing to do with the ropes or the candle...

Aubrey said...

Yeah, sad to say... I don't know the answer. Cameron? You sure you can't figure it out for us?

Cameron said...

From Google:

Alright, here's the answer. Light both ends of rope A and one end of rope B. After 30 minutes, rope A will be completely burned up and there will be 30 minutes of rope B left. Light the other end of rope B; it will burn up in 15 minutes. Total time elapsed since starting the ropes on fire: 45 minutes.

Aubrey said...

Ah....

Thank goodness for Google.

Carlos said...

I am still trying to find out how to get the fox, the hen and the wheat over to the island in the last word puzzle I was given--way back in high school.

Actually, I figured it out. You take the wheat, let the fox eat the chicken, he runs off and you are left with a nice pile of wheat to plant and no foxes or chickens.
What is not to like?