Con Fusing Puzzle - Solution
The Puzzle:
You know they burn for exactly one hour after you light them at one end.
But the entire fuse does not burn at a constant speed. For example, it might take five minutes to burn through half the fuse and fifty-five minutes to burn the other half.
With your lighter and using these fuses, how can you measure exactly three-quarters of an hour of time?
Our Solution:Light both ends of one fuse.
At the same time light one end of a second fuse.
The first fuse will finish in half an hour.
At that point the second fuse will be half done (in time, not necessarily in distance) and you immediately light its other end. The second half hour will now take only quarter of an hour.
Total time: half an hour plus quarter of an hour equals three-quarters of an hour.
At the same time light one end of a second fuse.
The first fuse will finish in half an hour.
At that point the second fuse will be half done (in time, not necessarily in distance) and you immediately light its other end. The second half hour will now take only quarter of an hour.
Total time: half an hour plus quarter of an hour equals three-quarters of an hour.