The ratio of incomes of two persons is $9:7$ and the ratio of their expenditures is $4:3$. If each of them manages to save ₹ $2000$ per month,find their monthly incomes.

Form the pair of linear equations in the following problems,and find their solutions (if they exist) by the elimination method.
Meena went to a bank to withdraw ₹ $2000$. She asked the cashier to give her ₹ $50$ and ₹ $100$ notes only. Meena got $25$ notes in all. Find how many notes of ₹ $50$ and ₹ $100$ she received.

Solve the following pair of linear equations by the substitution and cross-multiplication methods:
$8x + 5y = 9$
$3x + 2y = 4$

Solve the following pair of linear equations by the substitution method:
$\frac{3x}{2} - \frac{5y}{3} = -2$
$\frac{x}{3} + \frac{y}{2} = \frac{13}{6}$

Form the pair of linear equations in the following problems,and find their solutions graphically.
$5$ pencils and $7$ pens together cost ₹ $50$,whereas $7$ pencils and $5$ pens together cost ₹ $46$. Find the cost of one pencil and that of one pen.

Form the pair of linear equations for the following problem and find their solution by the substitution method.
The taxi charges in a city consist of a fixed charge together with the charge for the distance covered. For a distance of $10 \, km$,the charge paid is ₹ $105$ and for a journey of $15 \, km$,the charge paid is ₹ $155$. What are the fixed charges and the charge per $km$? How much does a person have to pay for travelling a distance of $25 \, km$?