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2 Fuses Problem
Difficulty Level

You have two lengths of fuse. Each will burn for exactly one hour. But the fuses are not necessarily identical and do not burn at a constant rate. There are fast-burning sections and slow-burning sections.
How do you measure forty-five minutes using only the fuses and a lighter?

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Step 1 : Burn the first fuse at both the ends and burn the 2nd fuse at one end at the same time. The first fuse will burn out in 30 mins.
Step 2 : When the first fuse burns out there will still be 30 mins left on the 2nd fuse. At this point, burn the other end of the 2nd fuse. The 2nd fuse will now burn out in next 15 mins.

We have thus measured 45 mins

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