53. By subtracting a certain number from the numerator of the fraction $\frac{537}{463}$ and adding it to the denominator, Tanya obtained $\frac{1}{9}$ after simplification. What number did she subtract from the numerator and add to the denominator?
53. $\frac{537-x}{463+x}=\frac{1}{9}$, hence $x=437$.