21 加法 31 等于多少？
21 + 31 = 52
21加法31 等于 52
竖式演算
验算
- 用减法验算：52 − 31 = 21
- 用减法验算：52 − 21 = 31
相关题目
21 + 30 = 51
21 + 32 = 53
21 + 29 = 50
21 + 33 = 54
21 + 28 = 49
21 + 34 = 55
21 + 35 = 56
21 + 27 = 48
20 + 31 = 51
22 + 31 = 53
19 + 31 = 50
23 + 31 = 54
24 + 31 = 55
18 + 31 = 49
25 + 31 = 56
17 + 31 = 48
1 + 51 = 52
2 + 50 = 52
3 + 49 = 52
4 + 48 = 52
5 + 47 = 52
6 + 46 = 52
35 + 52 = 87
50 + 13 = 63
30 + 64 = 94
51 + 6 = 57
17 + 60 = 77
30 + 27 = 57
65 - 13 = 52
57 - 5 = 52