Tính nhanh: 12345 * 17 + 23 * 12345 + 12345 + 12345 * 35 + 12345 * 24

12345 x 17 + 23 x 12345 + 12345 + 12345 x 35 + 12345 x 24

= 12345 x 17 + 23 x 12345 + 12345 x 1 + 12345 x 35 + 12345 x 24

= 12345 x (17 + 23 + 1 + 35 + 24)

= 12345 x 100

= 1234500