3 加法 21 等于多少？

3 + 21 = 24

3加法21 等于 24

竖式演算

3+2124

验算

  • 用减法验算：24 − 21 = 3
  • 用减法验算：24 − 3 = 21

相关题目

3 + 20 = 23 3 + 22 = 25 3 + 19 = 22 3 + 23 = 26 3 + 24 = 27 3 + 18 = 21 3 + 25 = 28 3 + 17 = 20 2 + 21 = 23 4 + 21 = 25 1 + 21 = 22 5 + 21 = 26 6 + 21 = 27 7 + 21 = 28 8 + 21 = 29 9 + 21 = 30 1 + 23 = 24 2 + 22 = 24 4 + 20 = 24 5 + 19 = 24 6 + 18 = 24 7 + 17 = 24 15 + 63 = 78 47 + 10 = 57 6 + 83 = 89 82 + 11 = 93 17 + 52 = 69 15 + 34 = 49 28 - 4 = 24 35 - 11 = 24