a) Tính 24 × (8 – 4) = …………………. = ………………….. 24 × 8 – 24 × 4 = ……………….. = ……………….. (9 – 3) × 8 = …………………… = …………………… 9 × 8 – 3 × 8
Giải thích
a)
24 × (8 – 4) = 24 × 4 = 96 | 24 × 8 – 24 × 4 = 192 – 96 = 96 |
(9 – 3) × 8 = 6 × 8 = 48 | 9 × 8 – 3 × 8 = 72 – 24 = 48 |
b)
24 × 8 – 24 × 4 = 24 × (8 – 4) 15 × 6 – 15 × 4 < 15 × (6 – 3) | 9 × 8 – 3 × 8 = (9 – 3) × 8 25 × (10 – 5) = 25 × 10 – 25 × 5 |