Question

 

\(5\frac{4}{7}:x=13\)

\(\frac{2}{3}\times x-0,5\times x=\frac{5}{12}\)

\(y-85\%\times y=1\frac{1}{5}\)

 

 

Answer 1

\(5\frac{4}{7}:x=13\)

=> \(x=\frac{39}{7}:13\)

=> \(x=\frac{3}{7}\)

Answer 2

\(\frac{2}{3}x-0,5x=\frac{5}{12}\)

\(\Leftrightarrow x\left(\frac{2}{3}-0,5\right)=\frac{5}{12}\)

\(\Leftrightarrow x\left(\frac{4}{6}-\frac{3}{6}\right)=\frac{5}{12}\)

\(\Leftrightarrow\frac{1}{6}x=\frac{5}{12}\)

\(\Leftrightarrow x=\frac{5}{12}\div\frac{1}{6}\)

\(\Leftrightarrow x=\frac{5}{2}\)

Answer 3

\(y-85\%y=1\frac{1}{5}\)

\(\Leftrightarrow y\left(1-85\%\right)=1\frac{1}{5}\)

\(\Leftrightarrow15\%x=1\frac{1}{5}\)

\(\Leftrightarrow\frac{15}{100}x=1\frac{1}{5}\)

\(\Leftrightarrow\frac{3}{20}x=\frac{6}{5}\)

\(\Leftrightarrow x=\frac{6}{5}\div\frac{3}{20}\)

\(\Leftrightarrow x=4\)