Question

Sanjay gets fixed monthly income every year and there is a certain increment in his salary. After 4 years, his monthly salary was Rs. $4500$ and after $10$ years his monthly salary become $5400$ rupees, then find his original salary and yearly increment.

Answer 1

Let Sanjay's monthly salary be 'x' rupees and yearly increment be 'y' rupees.

By first condition

$x+4y-4500$ ………….$\left(1\right)$

By second condition

$x+10y=5400$ ……………$\left(2\right)$

From equation - $\left(1\right)$ & $\left(2\right)$

Subtraction from $\left(2\right)$ - $\left(1\right)$

$x+10y=5400$

$x+4y=4500$

_______________

$6y=900$

$y=\frac{900}{6}$

$y=150$

Putting the value of $y=150$ in equation - $\left(1\right)$

$x+4y=4500$

$x+4\left(150\right)=4500$

$x+600=4500$

$x=4500-600$

$\therefore x=3900$

$\therefore$ Sanjay's original salary $x=3900$ rupees

$\therefore$ His monthly increment $y=150$ rupees.