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Classic Logical Interview Puzzle

60 minutes puzzleClassic Logical Interview Puzzle - 20 November

I have two rectangular wires.
Both of them have property that when i light the fire from one end , it will take 60 minutes to get completely burn.
However they do not burn at consistent speed (i.e it might be possible 1st 20% burn in 50 minutes and 80% can burn in 10 minutes).

So how could i measure 45 minutes ?

For Solution : Click Here


  1. Burn one rectangle wire @ both ends... counts 15 minutes, now burn the second one @ one end... counts 30 minutes... Done to count 45 minutes

  2. burn one rectangle wire @ both ends and one rectangle wire @ one end. first one will take 30 mins to burn completely. After first wire burn, burn the second wire @ another end. it will take 15 mins to burn the second wire (because second wire already burnt 30 mins so it has remaining 30 mins only).. so totally 45 mins


  3. take both wires ,

    burn all the four end of first wire (15 mins)

    when the first wire is burned out completly, burn two end of second wire(30 mins)

  4. burn both ends of 1st wire and one end of the 2nd wire. When the 1st wire burns out, just at that instant, light the other end of the 2nd wire.

  5. take a first rectangular wire and put fire any boundary point ,simultaneously strengthen the other rectangular wire and put fire on one end when the rectangle burns completely 30 mins are over then light the fire on the other end of second wire when second wire burns completely 45 mins' are over :P

  6. Sunil Finding Neverland is right

  7. Good Website For Engineering Students...