The cost of 5 pens and 8 pencils is Z 120, while the cost of 8 pens and 5 pencils is Z 153. Find the cost of 1 pen and that of 1 pencil.

Let us assume the cost of 1 pen is Rs x and that of pencil is Rs y

According to the question, we have


5x + 8y = 120 …(i)


8x + 5y = 153 …(ii)


Now, adding both the equations we get:


13x + 13y = 273


13 (x + y) = 273



x + y = 21 …(iii)


Now, by subtracting (i) from (ii) we get:


3x – 3y = 33


x – y = 11 …(iv)


By adding (iii) and (iv), we get:


2x = 32



Putting the value of x in (iii), we get


16 + y = 21


y = 21 – 16


y = 5


The cost of 1 pen is Rs. 16 and that of 1 pencil is Rs. 5


8