2.8 × 0.5 = 1.44.9 × 2 = 9.89.8 / 7 = 1.4
(1.4 + 1.4) / 3.5 = 0.80.8 - 2.2 = -1.4
Therefore, 2.8 × 0.5 + 4.9 × 2/7 / 3.5 : 0.7 - 2.2 = -1.4
2.8 × 0.5 = 1.4
4.9 × 2 = 9.8
9.8 / 7 = 1.4
(1.4 + 1.4) / 3.5 = 0.8
0.8 - 2.2 = -1.4
Therefore, 2.8 × 0.5 + 4.9 × 2/7 / 3.5 : 0.7 - 2.2 = -1.4