57 加法 21 等于多少？
57 + 21 = 78
57加法21 等于 78
竖式演算
验算
- 用减法验算：78 − 21 = 57
- 用减法验算：78 − 57 = 21
相关题目
57 + 20 = 77
57 + 22 = 79
57 + 19 = 76
57 + 23 = 80
57 + 24 = 81
57 + 18 = 75
57 + 25 = 82
57 + 17 = 74
56 + 21 = 77
58 + 21 = 79
55 + 21 = 76
59 + 21 = 80
60 + 21 = 81
54 + 21 = 75
61 + 21 = 82
53 + 21 = 74
1 + 77 = 78
2 + 76 = 78
3 + 75 = 78
4 + 74 = 78
5 + 73 = 78
6 + 72 = 78
41 + 28 = 69
96 + 2 = 98
49 + 50 = 99
12 + 30 = 42
66 + 20 = 86
45 + 33 = 78
90 - 12 = 78
100 - 22 = 78