$${{{{(469 + 174)}^2} - {{(469 - 174)}^2}} \over {(469 \times 174)}} = ?$$

$$\eqalign{ & \frac{{{{\left( {469 + 174} \right)}^2} - {{\left( {469 - 174} \right)}^2}}}{{\left( {469 \times 174} \right)}} = ? \cr & {\text{We}}\,{\text{ know that}}, \cr & 4ab = {\left( {a + b} \right)^2} - {\left( {a - b} \right)^2} \cr & \therefore \frac{{{{\left( {469 + 174} \right)}^2} - {{\left( {469 - 174} \right)}^2}}}{{\left( {469 \times 174} \right)}} \cr & = \frac{{4 \times 469 \times 174}}{{469 \times 174}} \cr & = 4 \cr} $$