There are two ships, a fast one and a slower one, each travel consistently at their own fixed speed.

If the fast ship travels in a straight line from Duxmouth to Boxcote and the slow ship travels from Axton to Caxcombe, and they each set off at the same time, they will collide where the routes cross.

Similarly, if the fast ship travels in a straight line from Caxcombe to Axton and the slow ship travels from Boxcote to Duxmouth, and they each set off at the same time, they will again collide where the routes cross.

If the fast ship travels from Caxcombe to Duxmouth and the slow ship from Axton to Boxcote, and they set off at the same time, clearly they won’t clash, as the routes don’t cross, but which ship will reach its destination first?