The value of $$\frac{{\sqrt {80} - \sqrt {112} }}{{\sqrt {45} - \sqrt {63} }} = ?$$

$$\eqalign{ & {\text{According to the question,}} \cr & \frac{{\sqrt {80} - \sqrt {112} }}{{\sqrt {45} - \sqrt {63} }} \cr & \Rightarrow \frac{{4\sqrt 5 - 4\sqrt 7 }}{{3\sqrt 5 - 3\sqrt 7 }} \cr & \Rightarrow \frac{{4\left( {\sqrt 5 - \sqrt 7 } \right)}}{{3\left( {\sqrt 5 - \sqrt 7 } \right)}} \cr & \Rightarrow \frac{4}{3} \cr & \Rightarrow 1\frac{1}{3} \cr} $$