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______ ．

If the molecules of this true fraction are x, then the denominator is x + 1, and the denominator plus 3 becomes x + 4, which can be obtained from the theme: X: (x + 4) = 4:5, and from the topic meaning: X: (x + 4) (X: (x + 4) = 4:5, and the following: X: (x + 4) (X: (x + 4) = 4:5, and from the topic meaning: X: (X: (x + 4) = 4:5, and the following: X: (X: (x + 4) = 4:5: 4:5:5, and from the topic meaning can be obtained: X: (X: (X: (X: (x + 4) 4: 4: 4:5:5:5, and & & nbsp; & nbsp; & & nbsp; & nbsp; & nbsp; & & nbsp; & & nbsp; & & nbsp; & & nbsp; & & nbsp; & & nbsp; & & nbsp; & & nbsp; & & nbsp; & & nbsp; & & nbsp; & & nbsp; & & nbsp; & & nbsp; & & nbsp; & & nbsp; & & nbsp; & nbsp; & & nbsp; & nbsp; & nbsp; & nbsp; & & nbsp; &X = 16; 16 + 1 = 17, so the original score is 1617. A: the original score is 1617