Tính nhẩm: a) 5 × 2 = . . . . . 5 × 8 = . . . . . b) 14 : 2 = . . . . . 16 : 2 = . . . . . 2 × 5 = . . . . . 2 × 7 = . . . . . 20 : 2 = . . . . . 8 : 2 = . . . . . 5 ×
Giải thích
a) 5 × 8 = 40 b) 16 : 2 = 8 |
2 × 5 = 10 2 × 7 = 14
20 : 2 = 10 8 : 2 = 4 |
5 × 3 = 15 5 × 9 = 40
15 : 5 = 3 20 : 5 = 4 |
2 × 9 = 18 2 × 8 = 16
40 : 5 = 8 35 : 5 = 7 |