Bài 1 (2,5 điểm) Thực hiện phép tính hợp lý (nếu có thể): a) $\frac{2}{3}$ + $\frac{3}{4}$.$\frac{4}{9}$ b) 4.($\frac{3}{4}$)² - 0,25 c) $\frac{1}{7}$.$\frac{3}{8}$ + $\frac{1}{7}$.$\frac{5}{8}$ + $\frac{(-1)^{2023}}{7}$ d) ($\frac{-2}{3}$)² + $\sqrt[]{\frac{49}{81}}$ - |$\frac{-7}{3}$| : 3

`2/3 + 4/3 * 4/9`

`= 2/3 + 1/3`

`= 3/3 = 1`

`---`

`4 * (3/4)^2  -0,25`

`= 4 * 9/16 - 1/4`

`= 9/4 - 1/4`

`= 2`

`---`

`1/7 * 3/8 + 1/7 * 5/8 + (-1)^2023/7`

`= 1/7 * 3/8 + 1/7 * 5/8 -1/7`

`= 1/7 * (3/8 + 5/8 -1)`

`= 1/7 * 0`

`= 0`

`---`

`(-2/3)^2 + \sqrt{49/81} - |-7/3| : 3`

`= 4/9 + 7/9 - 7/3 : 3`

`= 11/9 - 7/9`

`= 4/9`