2 7 x 100 1 July 8, 2019 16 32 64 128 15 15 x 2 7 x 15 100 2 x 100 7 x 10 A n 100 x 2 7 10 n 2 x 10.000 7 x 100 2 x 10 Tính nhanh 15 15 x 2 7 x 15 100 2 7×100 2 7 x 100 2 75 x 100