Question

A car takes 2 hours to reach a destination by travelling at the speed of 60 km/h. How long will it take when the car travels at the speed of 80 km/h?

Answer 1

Let the time taken by the car to reach the destination, while travelling with a speed of 80 km/hr, be x hours.

The following table is obtained:

Speed (in km/hr)	60	80
Time taken (in hours)	2	x

Hence, the speed of the car and the time taken by the car are inversely proportional to each other. Therefore,

∴ 80 × x = 60 × 2

⇒ `x = (60 × 2)/80`

⇒ `x = 3/2 = 1 1/2`

The time required by the car to reach the given destination is `1 1/2` hours.