Câu 1: (2 điểm) Thực hiện phép tính: a) $\frac{2}{7}$ + ($\frac{-17}{7}$) + $\frac{8}{7}$ b) $\frac{5}{9}$ : ($\frac{1}{11}$ - $\frac{5}{22}$) + $\frac{5}{9}$ : ($\frac{1}{15}$ - $\frac{2}{3}$) c) $\frac{(-2)³}{5}$.|$\frac{1}{4}$ - 1| + $2023^{0}$ d) -$\frac{5}{2}$.$\sqrt{\frac{9}{25}}$ - 2².|-$\frac{1}{4}$|

a) $\frac{2}{7}$ + ($\frac{-17}{7}$ ) + $\frac{8}{7}$

= $\frac{-15}{7}$ + $\frac{8}{7}$

=$\frac{-7}{7}$

= -1

b) $\frac{5}{9}$ ÷ ($\frac{1}{11}$ - $\frac{5}{22}$ ) + $\frac{5}{9}$ ÷ ($\frac{1}{15}$ - $\frac{2}{3}$ )

= $\frac{5}{9}$ ÷ ($\frac{2}{22}$ -$\frac{5}{22}$ ) + $\frac{5}{9}$ ÷ ($\frac{1}{15}$ - $\frac{10}{15}$)

= $\frac{5}{9}$ × $\frac{-22}{3}$ + $\frac{5}{9}$ × $\frac{-5}{3}$

= $\frac{5}{9}$ × ( $\frac{-22}{3}$ + $\frac{-5}{3}$)

= $\frac{5}{9}$ × $\frac{-27}{3}$

= $\frac{5}{9}$ × (-9)

= -5

c) $\frac{(-2)^3}{5}$ × | $\frac{1}{4}$ - 1| + $2023^{0}$ 

= $\frac{-8}{5}$ × $\frac{3}{4}$ + 1

= $\frac{-6}{5}$ + 1

= $\frac{-1}{5}$ 

d) -$\frac{5}{2}$ × $\sqrt[]{\frac{9}{25}}$ - $2^{2}$ × |$\frac{-1}{4}$ |

= -$\frac{5}{2}$ × $\frac{3}{5}$ - 4 × -$\frac{1}{4}$

= -$\frac{3}{2}$ - 1

= -$\frac{5}{2}$