Answer:
[tex]\sf Rs. \ 431\dfrac{73}{85} \quad or \quad Rs. \ 431.86[/tex]
Find the unit rate:
[tex]\rightarrow \sf 3\dfrac{7}{9} m = Rs. \ 212\dfrac{4}{5}[/tex]
[tex]\rightarrow \sf 1 m = Rs. \ \dfrac{212\dfrac{4}{5}}{3\dfrac{7}{9} }[/tex]
[tex]\rightarrow \sf 1 m = Rs. \ \dfrac{4788}{85} \quad or \quad Rs. \ 56\dfrac{28}{85}[/tex]
Then find the cost of 7 2/3m cloth:
[tex]\rightarrow \sf 7\dfrac{2}{3} \ m = Rs. \ \dfrac{4788}{85} \ * \ 7\dfrac{2}{3}[/tex]
[tex]\rightarrow \sf 7\dfrac{2}{3} \ m = Rs. \ \dfrac{36708}{85}[/tex]
[tex]\rightarrow \sf 7 \dfrac{2}{3} \ m = Rs. \ 431\dfrac{73}{85} \quad or \quad Rs. \ 431.86[/tex]