Q9 of 29 Page 3

The sum of the numerator and denominator of a fraction is 12. If the denominator is increased by 3, the fraction becomes 1/2. Find the fraction.

Let the numerator be ‘a’ and denominator be ‘b’.


Given, sum of the numerator and denominator of a fraction is 12.


⇒ a + b = 12 ……(1)


If the denominator is increased by 3, the fraction becomes 1/2 .


So,



⇒ 2a = b + 3


⇒ 2a – b = 3 …… (2)


Adding eq1 and eq2


⇒ a + b + 2a – b = 15


⇒ 3a = 15


⇒ a = 5


Thus, b = 7


Fraction is


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