In the question, two quantities I and II are given. You have to solve both the quantities to establish the correct relation between Quantity-I and Quantity-II and choose the correct option. Quantity I : A boat running downstream covers a distance of 20 km in 4 hrs, while for covering the same distance upstream it takes 5 hrs. Speed of boat in still water. (in kmph) Quantity II : A boat can cover a distance of 48 km in 3 hrs in still water. If speed of current is 4kmph, then the difference between time of boat to cover the same distance upstream (in hrs)