Cook the egg for 15 minutes #Riddle

You are trying to cook an egg for exactly fifteen minutes, but instead of a timer, you are given two ropes which burn for exactly 1 hour each. The ropes, however, are of uneven densities – i e , half the rope length-wise might take only two minutes to burn. How can you cook the egg for exactly fifteen minutes?

Cook the egg for 15 minutes #Riddle
Cook the egg for 15 minutes #Riddle