20 减法 1 等于多少？
20 - 1 = 19
20减法1 等于 19
竖式演算
验算
- 用加法验算：19 + 1 = 20
相关题目
20 - 2 = 18
20 - 3 = 17
20 - 4 = 16
20 - 5 = 15
20 - 6 = 14
20 - 7 = 13
20 - 8 = 12
20 - 9 = 11
19 - 1 = 18
21 - 1 = 20
22 - 1 = 21
18 - 1 = 17
23 - 1 = 22
17 - 1 = 16
24 - 1 = 23
16 - 1 = 15
21 - 2 = 19
22 - 3 = 19
23 - 4 = 19
24 - 5 = 19
25 - 6 = 19
26 - 7 = 19
75 - 28 = 47
55 - 7 = 48
56 - 39 = 17
61 - 19 = 42
54 - 26 = 28
40 - 24 = 16
2 + 17 = 19
3 + 16 = 19