Leerink Swann interview questions

You have rope that take 60 min to burn. Speed of burning is not uniform. Example: it doesn't take 30 min to burn half Using two ropes, how would you get 45 min? Answer: First Rope. Burn both ends at same time Second Rope: Burn only one side. when First rope is totally burn, it's been 30 min, now burn the rest of second rope both ends. Which should take additional 15 min. 30 + 15 = 45 min.