For a true fraction, the numerator and denominator are two continuous natural numbers. If 3 is added to the denominator, the fraction is 45. The original fraction is 45______ .

For a true fraction, the numerator and denominator are two continuous natural numbers. If 3 is added to the denominator, the fraction is 45. The original fraction is 45______ .

Let the numerator of the true fraction be x, then the denominator is x + 1, and the denominator plus 3 becomes x + 4