If x is the square of the number when $$\left( {\frac{2}{5}{\text{ of }}6\frac{1}{4} \div \frac{3}{7}} \right)$$    of $$1\frac{2}{7}$$ is divided by $$11\frac{1}{4},$$  then the value of 81x is:

Solution(By Examveda Team)

$$\eqalign{ & \frac{{\left( {\frac{2}{5}{\text{ of }}6\frac{1}{4} \div \frac{3}{7}} \right) \times 1\frac{2}{7}}}{{11\frac{1}{4}}} = \sqrt x \cr & \frac{{\left( {\frac{2}{5}{\text{ of }}\frac{{25}}{4} \div \frac{3}{7}} \right) \times \frac{9}{7}}}{{\frac{{45}}{4}}} = \sqrt x \cr & \frac{{\frac{5}{2} \times \frac{7}{3} \times \frac{9}{7}}}{{\frac{{45}}{4}}} = \sqrt x \cr & \frac{{15}}{2} \times \frac{4}{{45}} = \sqrt x \cr & x = \frac{4}{9} \cr & 81x = 81 \times \frac{4}{9} \cr & 81x = 36 \cr} $$