Jess rode 4.25 km in 20 min.
Speed = 4.25: 20 = 0.212 km/min
Corey rode 3.75 km in 18 min.
S= 3.75 : 18= 0.208
Mia rode 3.5 km in 17 min.
S = 3.5 :17 = 0.205
Zoey rode 3.6 km in 16 min.
S= 3.6 :16 = 0.225
The greatest rate of speed : ZOE with 0.225 km/min