21 乘法 1 等于多少？

21 × 2 = 42 21 × 3 = 63 21 × 4 = 84 21 × 5 = 105 21 × 6 = 126 21 × 7 = 147 21 × 8 = 168 21 × 9 = 189 20 × 1 = 20 22 × 1 = 22 19 × 1 = 19 23 × 1 = 23 24 × 1 = 24 18 × 1 = 18 25 × 1 = 25 17 × 1 = 17 1 × 21 = 21 3 × 7 = 21 7 × 3 = 21 30 × 4 = 120 6 × 23 = 138 49 × 50 = 2450 82 × 60 = 4920 27 × 83 = 2241 43 × 21 = 903 90 - 69 = 21 80 - 59 = 21 81 - 60 = 21 75 - 54 = 21 4 × 85 = 340