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
1.8 - 7 = 1
2.3 + 8 - 4 = 7
3.16 - 2 = 14
4.9 + 0 = 9
5.5 - 0 - 0 = 5
6.8 - 1 = 7
7.1 + 4 + 3 = 8
8.7 + 3 - 9 = 1
9.4 + 8 - 3 = 9
10.4 - 0 - 0 = 4
11.7 + 0 + 0 = 7
12.1 + 3 - 0 = 4
13.7 + 2 - 6 = 3
14.16 + 10 = 26
15.8 - 4 = 4
16.15 + 3 = 18
17.6 + 3 = 9
18.0 + 7 - 5 = 2
19.6 - 2 = 4
20.7 + 2 + 2 = 11
21.0 + 2 - 9 = -7
22.11 - 4 = 7
23.2 - 0 = 2
24.18 + 0 = 18
25.7 + 2 = 9
26.6 + 3 - 0 = 9
27.3 + 7 - 9 = 1
28.8 + 0 = 8
29.19 + 5 = 24
30.17 + 7 = 24
31.3 - 2 = 1
32.0 + 9 - 8 = 1
33.12 + 5 = 17
34.8 + 3 - 6 = 5
35.6 + 0 = 6
36.15 - 6 - 5 = 4
37.8 + 3 + 8 = 19
38.6 + 5 - 4 = 7
39.9 + 3 + 4 = 16