Răspuns:
Explicație:
a)
1 km = 1000 m
1 h = 3600 sec
1 km /h = > 1000 m / 3600 sec = 5/18 m/sec
72 km / h = 72 x 5/18 = 360 / 18 = 20 m/sec
b)
20 m ................. 1 sec
X m ................... 10 sec
X = 20 x 10 = 200 m distanta parcursa in 10 sec
c)
20 m .................. 1 sec
60 m .................. X sec
X = 60 : 20 = 3 sec se parcurc 60 m