1)
1 h 6'
1 h 6' = 1 h +6/60 h= 1,1 h
79,2 km : 1,1h =72 km/h
72 km =72x1000 =72000 m
1 h = 60 min = 60x60=3600 secunde
72 km/h= 72000m/3600s=20 m/s
2
V1=5m/s
V2=300 m/min =300 m/60s=5 m/s
V3=18km/h. =18 x 1000 m/60x60 s=18000/3600= 5 m/s
cele 3 vehicule se deplaseaza cu aceeasi viteza de 5m/s