Question

A travels a distance of 360 miles from bangalore to chennai in 4 hours at an average speed of 80mph. How much time will he take to cover the same distance if his average speed was 50mph?

Answer 1

Since,

less the speed, more will be the time taken to complete the journey,

Therefore, it is a case of inverse variation.

let,

the time taken by A to cover the distance at the average speed of 50mph be'y'

Hence:     80 x 4=  50 x y              <since xy is constant in inverse variation.>

Hence      360/50 = y

Hence        7.2 = y

      Therefore,

A will cover the journey in 7.2hrs

.