Brain Teasers and Puzzles


The Two Fuses


Simultaneously light both ends of one fuse plus only one end of the second fuse.

After thirty minutes, the first fuse would have burned completely through.

At that time, the second fuse will have burned halfway. Thus it has thirty minutes of burn time left in this condition.

Now, light the other end of the second fuse, causing it to burn twich as fast.

After fifteen more minutes, the second fuse will have completely burned through.

All total, 45 minutes have now elapsed.




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