A can travelling at a speed of 40 km/h can complete a journey in 9 hours. How long will it take to travel the same distance at 60 km/h?

Correct option is A

Given:

Speed₁ = 40 km/h, Time₁ = 9 hours
Speed₂ = 60 km/h
Distance is constant in both cases.

Concept Used:

When distance is constant, time is inversely proportional to speed.

Formula Used:

​$$\text{Time}_2 = \frac{\text{Speed}_1}{\text{Speed}_2} \times \text{Time}_1$$​​

Solution:​

​$$\text{Time}_2 = \frac{40}{60} \times 9 = \frac{2}{3} \times 9 = 6 \text{ hours}$$​​