KöMaL 2014 B4593

An ant starts crawling at constant speed from the left end of a 4-metre-long rubber rope towards the right end. It covers exactly one metre per minute. The rope is fixed at the left end, in a horizontal position. At the end of each minute, the rope is stretched uniformly by one metre. In which minute will the ant reach the right end of the rope? The ant is considered pointlike, the act of stretching takes negligible time, and the rope can be stretched to any length without breaking it.