A man takes 40 minutes to cover a certain distance at a speed of 9 km/h. If he walks with a speed of 12 km/h, he covers the same distance in:

Correct option is D

Given:

Speed of man =9km/hr

Time taken by man = 40min

Formula Used:

Distance = $$Speed \times Time$$​​

Solution:

Time in hour  $$= \frac{40}{60} = \frac{2}{3}hr$$​​

Distance = $$9 \times \frac{2}{3} = 6km$$​​

If speed is 12km/hr:

Time taken =$$\frac{6}{12} =\frac{1}{2}hr \times 60 = 30minutes$$​​