Burning Rope Puzzle (Solved)

Burning Rope Puzzle comes under basic puzzles asked in the interview.

Puzzle

You have two ropes of varying thickness and length. Each rope burns 🔥 in exactly 60 minutes. How can you measure 45 mins using only these two ropes.

Note: You can’t cut the rope in half because of varying thickness and you don’t have a timer or watch to measure the burning time.

Solution

1. Burn first rope at both the ends and the second rope at one end.
2. The first rope burns completely after half an hour since you burned it from both end. At this point, burn the other end of the second rope so now it will take 15 mins more to burn completely.

Phat! total time is 30 + 15 = 45 mins.