Question

Reena has pens and pencils which together are 40 in number. If she has 5 more pencils and 5 less pens, then number of pencils would become 4 times the number of pens. Find the original number of pens and pencils.

Answer 1

Let’s assume the number of pens and pencils be x and y, respectively. 

Forming equations according to the question, we have 

x + y = 40 … (i) 

(y+5) = 4(x-5) 

y + 5 = 4x – 20 

5 + 20 = 4x – y 

4x – y = 25 … (ii) 

Adding equation (i) and (ii), We get, 

x + 4x = 40 + 25 

5x = 65 

⇒ x = 13 

Putting x = 13 in equation (i), we get 

13 + y = 40 

⇒ y = 40 – 13 = 27 

Therefore, it’s found that the number of pens Reena has is 13 And, the number of pencils Reena has is 27.