2. 在○里填上“＞”“＜”或“=”。
①$9.6-2.7$○$7$
②$5.3+2.52$○$7.8$
③$11.6-2.3$○$9.3$
④$1.9+1.9$○$3.88$
⑤$2.34+5.7$○$8.01$
⑥$3.92-0.71$○$3.21$
⑦$5.2+8.8$○$12.21$
⑧$5.2-0.5$○$4.98$
⑨$1.97-1.26$○$0.72$
⑩$7.4+5.6$○$12.58$
⑪$4.75+2.25$○$7.1$
⑫$5.9+0.1$○$6.0$

①$9.6-2.7$＜$7$
②$5.3+2.52$＞$7.8$
③$11.6-2.3$＝$9.3$
④$1.9+1.9$＜$3.88$
⑤$2.34+5.7$＞$8.01$
⑥$3.92-0.71$＝$3.21$
⑦$5.2+8.8$＞$12.21$
⑧$5.2-0.5$＜$4.98$
⑨$1.97-1.26$＜$0.72$
⑩$7.4+5.6$＞$12.58$
⑪$4.75+2.25$＜$7.1$
⑫$5.9+0.1$＝$6.0$

3. 计算下面各题,能简算的要简算。
①$21.4+3.4+12.6$
③$13.46-5.21+7.56$
⑤$16.2-10.1-3.1$
②$8.6+7.5+21.5$
④$9.98+12.7-11.53$
⑥$63.77-(13.21+5.77)$

①
$21.4+3.4+12.6$
$=21.4+(3.4+12.6)$
$=21.4+16$
$=37.4$
②
$8.6+7.5+21.5$
$=8.6+(7.5+21.5)$
$=8.6+29$
$=37.6$
③
$13.46-5.21+7.56$
$=8.25+7.56$
$=15.81$
④
$9.98+12.7-11.53$
$=22.68-11.53$
$=11.15$
⑤
$16.2-10.1-3.1$
$=16.2-(10.1+3.1)$
$=16.2-13.2$
$=3$
⑥
$63.77-(13.21+5.77)$
$=63.77-5.77-13.21$
$=58-13.21$
$=44.79$

4. 用竖式计算。
①6.75+25.88=
④13.11-5.22=
⑦38.75+56.98=
②6.55-3.87=
⑤22.76+15.25=
⑧200.5-78.36=
③7.83+2.34=
⑥1.62-0.56=
⑨94.83+67.97=

①
```
6.75
+25.88
-------
32.63
```
$6.75+25.88=32.63$
②
```
6.55
3.87
-------
2.68
```
$6.55-3.87=2.68$
③
```
7.83
+ 2.34
-------
10.17
```
$7.83+2.34=10.17$
④
```
13.11
5.22
-------
7.89
```
$13.11-5.22=7.89$
⑤
```
22.76
+15.25
-------
38.01
```
$22.76+15.25=38.01$
⑥
```
1.62
0.56
-------
1.06
```
$1.62-0.56=1.06$
⑦
```
38.75
+56.98
-------
95.73
```
$38.75+56.98=95.73$
⑧
```
200.50
78.36
--------
122.14
```
$200.5-78.36=122.14$
⑨
```
94.83
+ 67.97
--------
162.80
```
$94.83+67.97=162.8$