Câu 3. Tính theo mẫu :

32 dam x 3 =   96dam                    96 cam : 3 = 32 cm.

25 m x 2 =                                     36 hm : 3 =

15 km x 4 =                                   70 km : 7 =

34 cm x 6 =                                   55 dm : 5 =

Giải:

25 m x 2 =     50 m                              36 hm : 3 = 12 hm

15 km x 4 =    60 km                           70 km : 7 = 10 km

34 cm x 6 =    204 cm                          55 dm : 5 = 11dm.