10以内的加法+10以内的减法+10以内的加减混合+10以内连加+10以内连减+10以内加减混合+11~20的加减法+20以内加法（进位） 计算题
1.12 + 9 = 21
2.4 + 7 - 3 = 8
3.1 + 1 - 3 = -1
4.1 + 0 = 1
5.4 + 5 - 3 = 6
6.20 + 1 = 21
7.5 - 2 = 3
8.6 + 0 + 6 = 12
9.0 - 0 - 0 = 0
10.3 + 3 + 6 = 12
11.1 - 0 = 1
12.3 + 9 - 4 = 8
13.18 + 8 = 26
14.6 + 1 - 6 = 1
15.3 + 2 + 7 = 12
16.16 + 6 = 22
17.15 + 1 = 14
18.12 - 6 - 1 = 5
19.1 + 2 = 3
20.0 + 5 - 6 = -1
21.5 - 2 = 3
22.0 + 2 - 6 = -4
23.1 + 6 - 1 = 6
24.3 + 6 - 2 = 7
25.8 + 1 - 0 = 9
26.5 + 5 + 6 = 16
27.8 + 1 - 2 = 7
28.8 - 1 - 0 = 7
29.1 + 1 - 1 = 1
30.2 + 4 - 2 = 4
31.0 + 9 + 8 = 17
32.13 + 5 = 18
33.2 - 1 = 1
34.15 + 8 = 7
35.20 - 8 = 12
36.5 - 0 = 5
37.2 - 1 = 1
38.9 - 0 = 9
39.6 - 3 = 3