①(67+33)×25-780
②310+390÷30-137
③72×125
④(920+438÷73)×34
⑤2.3+4.69+15.31+6.7
⑥9.14-1.43-4.57
⑦[510-(150+120)]÷16
⑧23×8+6×23-23×4