Bài 7 :

25m 7dm = 25,7 m

4dm 6cm = 4,6 dm

15dm 5mm = 15,05 mm

18m 2cm = 18,02 m

2 dam2 5 m2 = 2,05 dam2

1 km2 5 dam2 = 1,0005 km2

6 hm2 7 dam2 = 6,07 dam2

18 hm2 17 m2 = 18,0017 hm2

Bài 8 :

6/4 m = 6 4/10 m = 6m 4dm = 640 cm

7,6 dm = 7 6/10 dm = 7dm 6cm = 76 cm

52,5 dm = 52 5/10 dm = 52dm 5cm = 5250 mm

1,005 km = 1 5/1000 = 1km 5m = 1005 m

4,8 dam2 = 4 8/10 dam2 = 0 dam2 48 m2

9,05 dam2 = 9 5/10 dam2 = 9 dam2 5 m2 = 905 m2

5,1 hm2 = 5 1/10 hm2 = 5 hm2 1 dam2 = 51000 m2

3,4 km2 = 3 4/10 km2 = 3 km2 4 hm2 = 340 hm2

3,3 kg = 3 3/10 kg = 3kg 3 hg = 3300 g 

2,22 kg = 2 2/100 = 2kg 22hg = 2220 g 

Bài 9 :

126/100 = 1 26/100 = 1,26

1246/10 = 124 6/10 = 124,6

2001/1000 = 2 1/1000 = 2,001

340/100 = 3 40/100 = 3,40 = 3,4

29876/10000 = 2 9876/10000 = 2,9876

1002/100 = 10 2/100 = 10,02

3078/100 = 30 78/100 = 30,78

Bài 10 :

9/5 = 18/10 = 1,8

2/25 = 8/100 = 0,08

111/125 = 888/1000 = 0,888

23/8 = 2875/1000 = 2,875

76/4 = 304/100 = 3,04

42/25 = 168/100 = 1,68

370/50 = 740/100 = 7,40 = 7,4