3 х 5 = 15 - 3 + 3 + 3 + 3 + 3 = 15, 2 х 4 = 8 - 2 + 2 + 2 + 2 = 8, 6 x 2 = 12 - 6 + 6 = 12,

multiplication and repeated addition

排行榜

視覺風格

選項

切換範本

恢復自動保存: ?