\(y+y.\frac{1}{3}.\frac{9}{2}+y.\frac{7}{2}=25\)
\(y+y.6+y.\frac{7}{2}=25\)
\(y.\left(1+6+\frac{7}{2}\right)=25\)
\(y.\frac{21}{2}=25\)
\(y=25:\frac{21}{2}\)
\(y=25.\frac{2}{21}\)
\(y=\frac{50}{21}\)
\(y.5+y.3+y+y=50\)
\(y.\left(5+3+1+1\right)=50\)
\(y.10=50\)
\(y=5\)
\(y:4+y:3+y=\frac{5}{6}\)
\(y.\frac{1}{4}+y.\frac{1}{3}+y=\frac{5}{6}\)
\(y.\left(\frac{1}{4}+\frac{1}{3}+1\right)=\frac{5}{6}\)
\(y.\frac{19}{12}=\frac{5}{6}\)
\(y=\frac{5}{6}:\frac{19}{12}\)
\(y=\frac{5}{6}.\frac{12}{19}\)
\(y=\frac{10}{19}\)
