OK, this should take you more than a few seconds, it's a tough puzzle, but give it a go:
I'm quoting verbatim from the Web page: My Favorite Puzzles:
"You have two fuses that both last one hour, and you have no other ways of telling time. The fuses may be thicker at some points, so in half an hour, the amount of fuse that has burned may or may not be half the length of the whole fuse. How do you measure 45 minutes worth of time?"
Source: Tonya Khovanova
Shadblow Leaf Ecology
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Here are some shadblow (Amelanchier canadensis) or serviceberry leaves that
I collected from my yard this past Fall. Their tattered appearance speaks
of th...
9 years ago
Light one end of fuse one and both ends of fuse two. After 30 minutes fuse two will have burnt out. Light the remaining end of fuse 1 and fifteen minutes later fuse 1 will be completely burnt, measuring 45 minutes of time.
ReplyDeleteLight both ends of fuse A and one end of fuse B the same time. When fuse A runs out, light the other end of fuse B.
ReplyDeleteFuse A will last exactly one half-hour. When it burns out, one half of the total burn time of fuse B will remain. Lighting the other end of fuse B will cut its remaining burn time in half. Thus, 1/2 hour + 1/4 hour = 3/4 hour = 45 mins.
Damn--I missed your post, Mike. Good call, fine sir.
ReplyDelete