The value of $$\frac{\sqrt{0.6912} + \sqrt{0.5292}}{\sqrt{0.6912} - \sqrt{0.5292}}$$ is:

Expression : $$\frac{\sqrt{0.6912} + \sqrt{0.5292}}{\sqrt{0.6912} - \sqrt{0.5292}}$$

Using rationalization, = $$\frac{\sqrt{0.6912} + \sqrt{0.5292}}{\sqrt{0.6912} - \sqrt{0.5292}}$$ $$\times\frac{\sqrt{0.6912} + \sqrt{0.5292}}{\sqrt{0.6912} + \sqrt{0.5292}}$$

= $$\frac{(\sqrt{0.6912}+\sqrt{0.5292})^2}{(\sqrt{0.6912})^2-(\sqrt{0.5292})^2}$$

= $$\frac{0.6912+0.5292+2\sqrt{0.6912\times0.5292}}{0.6912-0.5292}$$

= $$\frac{1.2204+1.2096}{0.162}=15$$

=> Ans - (C)