Question

The time t required to drive afixed distance varies inversely as the speed r. It takes 5 hr at a speed of 80 km/h to drive a fixed distance. How long will it take t odrive the same distance at a speed of 70 km/hr?

Please help!


In an inverse dependence situation, the product of the two variables is a constant. In this rase, r x t = constant

Therefore
5 hr x 80 km/h = t x 70 km/h

t = (80/70) x 5 h = 5.714 hr
= 5 hr 42.9 min