a) \(\left(\dfrac{1}{4}x\right):3=\dfrac{5}{6}:\dfrac{1}{8}\\ \left(\dfrac{1}{4}x\right):3=\dfrac{20}{3}\\ \dfrac{1}{4}x=\dfrac{20.3}{3}\\ \dfrac{1}{4}x=20\\ x=80\)
a: Ta có: \(\dfrac{0.25x}{3}=\dfrac{5.6}{0.125}\)
\(\Leftrightarrow x\cdot\dfrac{1}{4}=134.4\)
hay x=537,6
b: Ta có: \(\dfrac{2.5}{7.5}=x:\dfrac{3}{5}\)
\(\Leftrightarrow x:\dfrac{3}{5}=\dfrac{1}{3}\)
hay \(x=\dfrac{1}{5}\)
\(\dfrac{5}{2}:\dfrac{15}{2}=x:\dfrac{7}{5}\\ x:\dfrac{7}{5}=\dfrac{1}{3}\\ x=\dfrac{7}{15}\)