The distance is the same that was covered.
Distance is speed multiplied by time.
Mr O takes 30 minutes and Mr Gordon takes 1 hour.
So the speed of Mr O is given by:
![\text{Speed}=\frac{10.5\operatorname{km}}{1hr}=10.5\operatorname{km}\text{ /hr}]()
Convert the speed in meter per second.

The speed of mr G is:
![S_G=(10.5)/(0.5)=21\operatorname{km}\text{ /hr=}(35)/(6)m\text{ /s}]()
So the difference between the speeds is:

So Mr O is 2.9167 m/s faster than Mr Gordon.