\(2x-\left(0,5+\dfrac{2}{3}\right):2\dfrac{1}{3}=0,25\\ \Rightarrow2x-\dfrac{5}{6}:\dfrac{7}{3}=\dfrac{1}{4}\\ \Rightarrow2x-\dfrac{5}{14}=\dfrac{1}{4}\\ \Rightarrow2x=\dfrac{17}{28}\\ \Rightarrow x=\dfrac{17}{56}\)

Áp dụng tính chất dãy tỉ số bằng nhau, ta có:

          \(\dfrac{x}{4}=\dfrac{y}{5}=\dfrac{z}{6}=\dfrac{x+y-z}{4+5-6}=\dfrac{9}{3}=3\)

Vì \(\dfrac{x}{4}=3\Rightarrow x=12\\\dfrac{y}{5}=3\Rightarrow y=15\\ \dfrac{z}{6}=3\Rightarrow z=18.\)

\(8-A\\ 9-C\\ 10-B\\ 11-C\\ 12-A\\ 13-D\\ 14-C\\ 15-D\\ 16-A\)