①4×3.7×2.5
②1.3+4.7×0.9
③19.92+16.6﹣9.92
④8.2×6.4﹣6.4×7.2
⑤1.7+17×9.9
4×4.38×2.5
34.8-(14.8+3.4)
1.87+1.87×99
15.42+6.78-2.42
3.6×197-97×3.6
(7.8-5.8)×2.4+3.6