Puzzle 1 | (How to Measure 45 minutes using two identical wires?)

How do we measure forty-five minutes using two identical wires, each of which takes an hour to burn? We have matchsticks with us. The wires burn non-uniformly. So, for example, the two halves of wire might burn in 10 minutes and 50 minutes respectively


If we light a stick, it takes 60 minutes to burn completely. What if we light the stick from both sides? It will take exactly half the original time, i.e. 30 minutes to burn completely.

  1. 0 minutes – Light stick 1 on both sides and stick 2 on one side.
  2. 30 minutes – Stick 1 will be burnt out. Light the other end of stick 2.
  3. 45 minutes – Stick 2 will be burnt out. Thus 45 minutes is completely measured.

Source: https://www.geeksforgeeks.org/forums/topic/measuring-45-minutes-using-two-identical-wires/

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