81 乘法 20 等于多少？

81 × 19 = 1539 81 × 21 = 1701 81 × 22 = 1782 81 × 18 = 1458 81 × 23 = 1863 81 × 17 = 1377 81 × 24 = 1944 81 × 16 = 1296 80 × 20 = 1600 82 × 20 = 1640 83 × 20 = 1660 79 × 20 = 1580 84 × 20 = 1680 78 × 20 = 1560 85 × 20 = 1700 77 × 20 = 1540 18 × 90 = 1620 20 × 81 = 1620 27 × 60 = 1620 30 × 54 = 1620 36 × 45 = 1620 45 × 36 = 1620 53 × 63 = 3339 17 × 42 = 714 7 × 46 = 322 76 × 49 = 3724 55 × 14 = 770 12 × 59 = 708 24 × 6 = 144 49 × 12 = 588