31 加法 21 等于多少？
31 + 21 = 52
31加法21 等于 52
竖式演算
验算
- 用减法验算：52 − 21 = 31
- 用减法验算：52 − 31 = 21
相关题目
31 + 20 = 51
31 + 22 = 53
31 + 19 = 50
31 + 23 = 54
31 + 24 = 55
31 + 18 = 49
31 + 25 = 56
31 + 17 = 48
30 + 21 = 51
32 + 21 = 53
29 + 21 = 50
33 + 21 = 54
28 + 21 = 49
34 + 21 = 55
35 + 21 = 56
27 + 21 = 48
1 + 51 = 52
2 + 50 = 52
3 + 49 = 52
4 + 48 = 52
5 + 47 = 52
6 + 46 = 52
65 + 4 = 69
61 + 4 = 65
53 + 2 = 55
44 + 3 = 47
27 + 71 = 98
21 + 61 = 82
81 - 29 = 52
26 × 2 = 52