You have 2 fuses and a lighter. When each fuse is lit, it takes exactly one hour to burn from one end to the other. You can assume that both of the fuses are identical.
Using only those 2 fuses and the lighter, how would you measure a period of exactly 45 minutes?
We burn fuse # 1 from both ends, and we burn fuse #2 from only one end. Then, after 30 minutes has passed, we can burn the other end of fuse #2. Fuse #2 would finish burning in 15 minutes because it has already has 30 minutes worth of time burned from it, but it is also burning from both ends – so that cuts the burning time in half. And 30 + 15 would give us 45 minutes
Read full article from 2 Fuses Problem Measure 45 Minutes
Using only those 2 fuses and the lighter, how would you measure a period of exactly 45 minutes?
We burn fuse # 1 from both ends, and we burn fuse #2 from only one end. Then, after 30 minutes has passed, we can burn the other end of fuse #2. Fuse #2 would finish burning in 15 minutes because it has already has 30 minutes worth of time burned from it, but it is also burning from both ends – so that cuts the burning time in half. And 30 + 15 would give us 45 minutes
Read full article from 2 Fuses Problem Measure 45 Minutes
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