1. 直接写出得数。
2.7+3=
10-3.7=
2.2-1.5=
4.7+0.3-0.2=
3.2+5.4=
2.8-1.6=
9.6-7.4=
5.6-0.1-0.2=
4.7-3.6=
8.5+6.2=
10.8-0.9=
0.8+1.2+2.9=
1.6+7.8=
7.6-0.9=
8.1-1.9=
0.95+0.05-1=
5.8-4.9=
5.92-3.8=
5.4+8.3=
6.6-2.7+1.3=
2.5+10.8=
0.1+0.99=
3.16-2.11=
0.14+6-2.4=
15.2-4.8=
6.9+6.9=
5-1.24=
4-1.7+2.6=
0.73+1.3=
16.6+0.9=
3.18+0.72=
9.6-2.4+2.8=

1. 5.7 6.3 0.7 4.8 8.6 1.2 2.2 5.3 1.1 14.7 9.9 4.9 9.4 6.7 6.2 0 0.9 2.12 13.7 5.2 13.3 1.09 1.05 3.74 10.4 13.8 3.76 4.9 2.03 17.5 3.9 10

2. 用竖式计算。
3.92+4.85=
9.2-6.54=
80-2.37=
32.54+21.7=
36.58-9.11=
24.2+3.95=

2. 8.77 2.66 77.63 54.24 27.47 28.15 竖式略

3.92+4.85=8.77
```
3.92
+ 4.85
------
8.77
```
9.2-6.54=2.66
```
9.20
6.54
------
2.66
```
80-2.37=77.63
```
80.00
2.37
------
77.63
```
32.54+21.7=54.24
```
32.54
+21.70
------
54.24
```
36.58-9.11=27.47
```
36.58
9.11
------
27.47
```
24.2+3.95=28.15
```
24.20
+ 3.95
------
28.15
```

3. 用计算器计算。
10.75+6.98-8.462=
36-12.93+34.77=
4.85+25.36-29.38=
12.58-3.46-4.33=

3. 9.268 57.84 0.83 4.79

0.8+0.88=
0.8+0.88+0.888=
0.8+0.88+0.888+0.8888=
0.8+0.88+0.888+…+0.88888888=

1.68 2.568 3.4568 7.01234568