5 pencils and 7 pens together cost Rs 195 while 7 pencils and 5 pens together cost Rs 153. Find the cost of each one of the pencil and pen.

Let the cost of each pencil be Rs. x and that of each pen be Rs. y. 

Then, we have: 

5x + 7y = 195 ………(i) 

7x + 5y = 153 ………(ii) 

Adding (i) and (ii), we get: 

12x + 12y = 348 

⇒ 12(x + y) = 348 

⇒ x + y = 29 ………(iii) 

Subtracting (i) from (ii), we get: 

2x – 2y = –42

⇒ 2(x – y) = –42 

⇒ x – y = –21 ………(iv) 

On adding (iii) and (iv), we get: 

4 + y = 29 

⇒ y = (29 – 4) = 25 

Hence, the cost of each pencil is Rs. 4 and the cost of each pen is Rs. 25.

Let the cost of each pencil be Rs. x and that of each pen be Rs. y. 

Then, we have: 

5x + 7y = 195 ………(i) 

7x + 5y = 153 ………(ii) 

Adding (i) and (ii), we get: 

12x + 12y = 348 

⇒ 12(x + y) = 348 

⇒ x + y = 29 ………(iii) 

Subtracting (i) from (ii), we get: 

2x – 2y = –42

⇒ 2(x – y) = –42 

⇒ x – y = –21 ………(iv) 

On adding (iii) and (iv), we get: 

4 + y = 29 ⇒ y = (29 – 4) = 25 

Hence, the cost of each pencil is Rs. 4 and the cost of each pen is Rs. 25.