Let the numerator be ‘a’ and denominator be ‘b’.
Given,
Sum of the numerator and denominator of a fraction is 3 less than twice the denominator.
⇒ a + b = 2b – 3
⇒ a = b – 3 ------ (1)
Also,
If the numerator and denominator are decreased by 1, the numerator becomes half the denominator.
⇒ a – 1 = (b – 1)/2
⇒ b = 2a - 1 ------ (2)
Substituting value of b in eq1.
⇒ a = 2a – 1 – 3
⇒ a = 4.
Thus,
b = 2 × 4 – 1 = 7