Burning Ropes
You have two ropes and a lighter. Each rope takes exactly 60 minutes to burn end to end, but burns non-uniformly (half the rope may take 5 minutes or 55). Using only these ropes, you can measure exactly 45 minutes. In the standard solution, what is the total number of rope ends you must light?
Related problems & prerequisites
Worth solving first
- The Die Hard Jugs 6.0/10
- Three Switches, One Bulb 6.0/10
- The Bridge at Night 5.0/10
Source: Classic rope-burning timing puzzle in wide circulation; no traceable original source. Statement written for AxiomIQ.