If $\frac{x}{2} = \frac{6}{y} = 3$,then $x + y = \ldots$

Aruna has only $Rs. 1$ and $Rs. 2$ coins with her. If the total number of coins that she has is $50$ and the amount of money with her is $Rs. 75$,then the number of $Rs. 1$ and $Rs. 2$ coins are,respectively

If the sum and the difference of the digit at the ten's place and the digit at the unit's place of a two-digit number are the same,then the digit at the unit's place is ...........

Solve the following pair of linear equations by the method of substitution: $2x - y + 3 = 0$ and $y = 2x - \frac{3}{2}$.

Solve the following pair of linear equations by the cross-multiplication method:
$3x + y = 7$
$2x + 3y = 14$

Solve the following pair of linear equations in two variables using the graphical method: $2x + y = 7$ and $x - 2y = 6$.