=（3.6+7.4）-（2.8+7.2）
=11-10
=1；
②（1-0.05）÷1.9+0.1
=0.95÷1.9+0.1
=0.5+0.1
=0.6；
③
| 4 |
| 29 |
| 3 |
| 4 |
| 3 |
| 8 |
=
| 4 |
| 29 |
| 3 |
| 8 |
=
| 4 |
| 29 |
| 5 |
| 8 |
=
| 5 |
| 58 |
④
| 8 |
| 17 |
| 1 |
| 23 |
| 9 |
| 17 |
=（
| 8 |
| 17 |
| 9 |
| 17 |
| 1 |
| 23 |
=1×
| 1 |
| 23 |
=
| 1 |
| 23 |
| 4 |
| 29 |
| 3 |
| 4 |
| 3 |
| 8 |
| 8 |
| 17 |
| 1 |
| 23 |
| 9 |
| 17 |
| 4 |
| 29 |
| 3 |
| 4 |
| 3 |
| 8 |
| 4 |
| 29 |
| 3 |
| 8 |
| 4 |
| 29 |
| 5 |
| 8 |
| 5 |
| 58 |
| 8 |
| 17 |
| 1 |
| 23 |
| 9 |
| 17 |
| 8 |
| 17 |
| 9 |
| 17 |
| 1 |
| 23 |
| 1 |
| 23 |
| 1 |
| 23 |