Question

An athlete covers 1500 m in 4 minutes. Calculate his speed in m/s and km/h.

Answer 1

We know:
1 km = 1000 m
And,
1 h = 60 min
= (60 $\times$ 60) s
= 3600 s

Now,

Distance travelled by the athlete = 1500 m
= (1500/1000) km
= 1.5 km
Time taken = 4 min
= 4/60 h
= 1/15 h or (4 $\times$ 60) s
= 240 s

Speed in m/s:
Speed = Distance/Time
= 1500/240
= 6.25 m/s

Speed in km/h:
Speed = Distance/Time
= 1.5/(1/15)
= 22.5 km/h