If $2x + y = 17$,$y + 2z = 15$,and $x + y = 9$,then the value of $4x + 3y + z$ equals:

$\frac{3}{5}$ of $\frac{4}{7}$ of $\frac{5}{9}$ of $\frac{21}{24}$ of $504 = ?$

$(2 + \frac{3}{x}) \times (y + \frac{1}{2}) = \frac{31}{4}$,find the values of $x$ and $y$ if $x$ and $y$ are positive integers.

What will come in the place of the question mark $(?)$ in the following expression?
$\frac{28}{65} \times \frac{195}{308} \div \frac{39}{44} + \frac{5}{26} = ?$

The simplification of $1+\frac{1}{1+\frac{1}{1-\frac{2}{3}}}$ yields the result

If $x^{3}+3x^{2}+3x=7,$ then $x$ is equal to