a)\(\frac{1}{3}+\frac{2}{3}:x=4-\frac{1}{2}\) b)\(0,5-x:\frac{1}{2}=\frac{1}{5}\)
\(\frac{1}{3}+\frac{2}{3}:x=\frac{7}{2}\) \(\frac{1}{2}-x:\frac{1}{2}=\frac{1}{5}\)
\(\frac{2}{3}:x=\frac{7}{2}-\frac{1}{3}\) \(x:\frac{1}{2}=\frac{1}{2}-\frac{1}{5}\)
\(\frac{2}{3}:x=\frac{19}{6}\) \(x:\frac{1}{2}=\frac{3}{10}\)
\(x=\frac{2}{3}:\frac{19}{6}\) \(x=\frac{3}{10}x\frac{1}{2}\)
\(x=\frac{4}{19}\) \(x=\frac{3}{20}\)