Question : Three numbers are in the ratio $\frac{4}{5}: \frac{5}{6}: \frac{9}{10}$. The difference between the smallest and the greatest numbers is 12. Find the number which is neither the smallest nor the greatest.

Question : Which of the following is the smallest ratio?
$\frac{5}{6}, \frac{7}{9}, \frac{11}{12}, \frac{13}{18}$

Question : Choose the option in which the numbers are in the correct ascending order.

Question : Let $x=\frac{5 \frac{3}{4}-\frac{3}{7} \times 15 \frac{3}{4}+2 \frac{2}{35} \div 1 \frac{11}{25}}{\frac{3}{4} \div 5 \frac{1}{4}+5 \frac{3}{5} \div 3 \frac{4}{15}}$. When $y$ is added to $x$, the result is $\frac{7}{13}$. What is the value of $y$?

Question : If $(x-\frac{1}{3})^2+(y-4)^2=0$, then what is the value of $\frac{y+x}{y-x}$?