How to measure 45 minutes using two wires

Problem: 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 a wire might burn in 10 minute and 50 minutes respectively.

Solution: We know that the wires are not uniform so we can't say that after 30 minutes half of the wire would have burnt but what we can guarantee is if we burn the wire from both sides then the wire will be burnt in 30 minutes (60 / 2). With this approach we can solve this puzzle easily. Here is how:

1. Burn the Wire-1 from both side and Wire-2 from single side.
2. Once the Wire-1 is completely burnt means 30 minutes we burn the Wire-2 from the other side too.
3. Now the Wire-2 will be completely burnt in next 15 minutes as for 30 minutes it is already burnt from single side and 30 minutes were remaining. As we have started fire from the other end too it will take only 15 (30 / 2) minutes to be fully burnt.