2.6+1.4×3 (8+0.8)×12.5
80×3.9×1.25 15.2×9.9+1.52
3.9×8.6+3.9×1.4 4.8×3.5-10.9
4×4.38×2.5
34.8-(14.8+3.4)
1.87+1.87×99