Question

A fraction becomes 3/12. when 2 is subtracted from the numerator and it becomes 5/20. when 8 is added to its denominator. Find the fraction. (a) 4/12 (b) 3/13 (c) 5/12 (d) 11/7​

Answer 1

Given :-

A fraction becomes 1/3 when 1 is subtracted from the numerator.

It become 1/4 when 8 is added to its denominator.

Solution :-

Let the fraction be x/y    

           

According to the question,                  

⇒ x–1/y = 1/3                  

⇒ 3x – y = 3... (i)                  

⇒ x/y + 8 = 1/4                  

⇒ 4x – y = 8 ... (ii)                  

Subtracting equation (i) from equation (ii), we get                  

⇒ x = 5 ... (iii)                  

Putting this value in equation (i), we get                  

⇒ 15 – y = 3                  

⇒ y = 12                  

Hence, the fraction is 5/12.