口算
| 400÷50= | 27×30= | 631-198= | 125×5×8= |
| 33+67= | 720÷90= | 90×40= | 18×5+4= |
| 350÷70= | 80×120= | 29×200= | (60×25)×4= |
| 400÷50= | 27×30= | 631-198= | 125×5×8= |
| 33+67= | 720÷90= | 90×40= | 18×5+4= |
| 350÷70= | 80×120= | 29×200= | (60×25)×4= |