Tính (theo mẫu) Mẫu: 9dam + 4dam = 13dam 18hm – 6hm = 12hm
Giải thích
6 dam + 15dam = 21dam 16hm – 9hm = 7hm
52dam + 37dam = 89dam 76dam – 25dam = 51 dam
48dam + 23dam = 71dam 63hm – 18hm = 45hm
6 dam + 15dam = 21dam 16hm – 9hm = 7hm
52dam + 37dam = 89dam 76dam – 25dam = 51 dam
48dam + 23dam = 71dam 63hm – 18hm = 45hm