Question

The time t required to drive a certain distance varies inversely with the speed r. If it takes 2 hours to drive the distance at 30 miles per hour, how long will it take to drive the same distance at 50 miles per hour?

Answer 1

Distance = r x t ===> t=d/r

Distance (after 2 hours driving @30mil/hr) = 2 x 30 = 60 Mil

To drive same distance (60)  with r = 50, the time needed is 60/50 =1.2 hrs