Question

A person crosses 600 metres long street in 5 min.what is his speed in km per hour?

Answer 1

600 meters=600/1000 km=3/5 km
5 min=5/60 hr=1/12 hr
So his speed in km/h is
D/T
=3/5/(1/12)
=3/5*12
=36/5
= 7.20 km/hr.
Ans>His speed is 7.20 km/h.

Answer 2

you can also find the answer in metre/sec and then multiply it by 18/5 to get the answer in km/hr.
the previous method is more mark fetching, this is a shortcut.