21 加法 20 等于多少？
21 + 20 = 41
21加法20 等于 41
竖式演算
验算
- 用减法验算：41 − 20 = 21
- 用减法验算：41 − 21 = 20
相关题目
21 + 19 = 40
21 + 21 = 42
21 + 22 = 43
21 + 18 = 39
21 + 23 = 44
21 + 17 = 38
21 + 24 = 45
21 + 16 = 37
20 + 20 = 40
22 + 20 = 42
19 + 20 = 39
23 + 20 = 43
24 + 20 = 44
18 + 20 = 38
25 + 20 = 45
17 + 20 = 37
1 + 40 = 41
2 + 39 = 41
3 + 38 = 41
4 + 37 = 41
5 + 36 = 41
6 + 35 = 41
15 + 74 = 89
44 + 40 = 84
61 + 8 = 69
73 + 14 = 87
33 + 13 = 46
8 + 51 = 59
83 - 42 = 41
71 - 30 = 41