Suppose you have a rubber band, and a point is marked on the rubber band at the 1/3 point. If you now apply force to the two ends of the rubber band to stretch it, will the point maintain its 1/3 position on the new rubber band? That is, is the marked point still the 1/3 point of the rubber band? If not, what is its position, and how do I calculate the position for the 1/4 point or 2/5 point, say?