Mohan takes 2 hours more than Kishore to walk 63 km. If Mohan increases his speed by 50%, then he can make it in 1 hour less than Kishore. How much time does Kishore take to walk 63 km?

7 hours

Speed is increased by 50%

50% = \(\frac{1}{2}\)

Ratio of ,    Old speed   :   New speed 

                         2        :      3

Old speed = 2s km/h

New speed = 3s km/h

Actual time = t hours

Initial time = ( t + 2 ) hours

Final time = ( t - 1 ) hours

We know that,

Distance = Speed x Time

63 = \(\frac{S1 × S2 }{S2 - S1}\) × ( t1 - t2 )

63 = \(\frac{3s × 2s }{3s - 2s}\) × ( t + 2  - t + 1 )

63 = 6s × 3

s = 3.5

Now, Initial speed of Mohan = 2s = 2 x 3.5 = 7 km/h

Time taken by Mohan = \(\frac{63}{7}\) = 9 hours

Time taken by kishore = 9 - 2 = 7 hours