Brain Teaser – 2 Ropes
I have come across several brain-teasers either through interviews or from talking with others so I thought I would start throwing these out to the readers as a good way to exercise the brain. So, here is the first one:
You are given 2 pieces of rope that are exactly 6 feet long each and a box of matches. Each rope is flammable and takes exactly 1 hour to burn. Each rope burns at a different and inconsistent rate (ie: it might take 10 seconds for the first 5 feet of rope to burn and the remaining 59 minutes and 50 seconds for the last foot of rope to burn).
How do you know when exactly 45 minutes has passed?
I have turned off comments for the post. If you would like to send me your answer for validation, send it to: willcrowthers@gmail.com. I will reveal the answer and the guesses I received next week.
Good luck.
