In railway trains,tea/coffee is served in earthen pots and disposal cups made of paper?What are the harms of it?

A passenger train and a goods train are running in the same direction on parallel railway tracks. If the passenger train now takes three times as long to pass the goods train, as when they are running in opposite directions, then what is the ratio of the speed of the passenger train to that of the goods train ? (Assume that the trains nm at uniform speeds)