21 加法 10 等于多少？
21 + 10 = 31
21加法10 等于 31
竖式演算
验算
- 用减法验算：31 − 10 = 21
- 用减法验算：31 − 21 = 10
相关题目
21 + 11 = 32
21 + 9 = 30
21 + 12 = 33
21 + 8 = 29
21 + 13 = 34
21 + 7 = 28
21 + 14 = 35
21 + 6 = 27
20 + 10 = 30
22 + 10 = 32
19 + 10 = 29
23 + 10 = 33
24 + 10 = 34
18 + 10 = 28
25 + 10 = 35
17 + 10 = 27
1 + 30 = 31
2 + 29 = 31
3 + 28 = 31
4 + 27 = 31
5 + 26 = 31
6 + 25 = 31
40 + 12 = 52
2 + 34 = 36
21 + 37 = 58
17 + 40 = 57
41 + 20 = 61
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51 - 20 = 31
79 - 48 = 31