A man walking at the speed of 4 km/h covers a certain distance in 6 hours and 15 minutes. If he covers the same distance by cycle in 5 hours and 10 minutes, then the speed of the cycle in km/h is:

Correct option is C

Given:
Speed of man while walking = 4 km/h
Time taken to cover certain distance = 6 hrs 15 mins
Time taken by cycle to cover the same distance = 5 hrs 10 mins
Formula Used:
Speed = $$\frac{Distance}{Time}$$​​
Solution:
Firstly, the time should be in hours, so
1 hour = 60 mins
15 mins = $$\frac{15}{60}=\frac{1}{4}=0.25$$​ hours
Total time taken by walking = 6 + 0.25 = 6.25 hours
Putting the values in the formula, we get
4= $$\frac{Distance}{6.25}$$​​
Distance, d = 4 × 6.25 = 25 km
Time taken by cycle to cover 25 kms = 5 hrs 10 mins
10 mins = 10/60≈0.167 hours
Total time taken = 5 + 0.167 = 5.167 hours
Speed of cycle = $$\frac{25}{5.167}=4.838 km/h=4 \frac{26}{31}km/h$$​​