5 pens and 6 pencils together …

Let the cost of a pen be Rs x and that of a pencil be Rs y.
As per given condition, Cost of 5 pens and 6 pencils is Rs.9
Then, 5x + 6y = 9 ............(i)
And Cost of 3 pens and 2 pencils is Rs.5.
So, 3x + 2y = 5 ...........(ii)
Multiplying equation (i) by 2 and equation (ii) by 6, we get
10x + 12y = 18 ...........(iii)
18x + 12y = 30 ...........(iv)
Subtracting equation (iii) from equation (iv), we get
(18x + 12y) -(10x + 12y)  = 30 - 18
{tex}\Rightarrow{/tex} 18x - 10x + 12y - 12y = 12
{tex}\Rightarrow{/tex} 8x = 12
{tex}\Rightarrow x = \frac{{12}}{8} = \frac{3}{2} = 1.5{/tex}
Substituting x =1.5 in equation (i), we get
{tex}5 ( 1.5) + 6y = 9{/tex}
{tex}7.5 + 6y = 9{/tex}
6y = 1.5
{tex}y = \frac{{1.5}}{6} = 0.25{/tex}
Hence, the cost of one pen = Rs.1.50 and the cost of one pencil = R.s 0.25