a)
7 hm + 70 cm = ? dm
7 hm = 700 dm
70 cm = 7 dm
700 dm + 7 dm = 707 dm
b)
2 km + 200 m = ? hm
2 km = 200 hm
200 m = 2 hm
200 hm + 2 hm = 202 hm
c)
80 dam - 800 m = ? dm
80 dm = 8000 dm
800 m = 8000 dm
8000 dm - 8000 dm = 0 dm
d)
7 km - 300 cm = ? m
7 Km = 7000 m
300 cm = 3 m
7000 m - 3 m = 6997 m