Answer :
Melania walked her 2 2/5 dog miles. Cathy walked her dog 1 3/4 times as far as Melania did.
1 3/4 times of 2 2/5 is
[tex]\begin{gathered} 1\frac{3}{4}\times2\frac{2}{5}=\frac{7}{4}\times\frac{12}{5} \\ =\frac{21}{5} \\ =4\frac{1}{5}^{} \end{gathered}[/tex]Now,
[tex]\begin{gathered} 4\frac{1}{5}-2\frac{2}{5}=\frac{21}{5}-\frac{12}{5} \\ =\frac{9}{5} \\ =1\frac{4}{5} \end{gathered}[/tex]So, Cathey walked her dog 1 4/5 miles more that Melenia.