Returning to the original problem, we ask how simplifying it can help us. If we realize that the size of the locomotive plays no role in the solution of the simplified problem, then the answer is not difficult. Suppose we first attach L to car B and consider it as one unit LB –as if it were the locomotive. Then by following the procedure above, we can move A to the right of LB, not just to the right of L. This leaves the position shown in Figure 1.41