a)\(\frac{143}{363}=\frac{13.11}{33.11}=\frac{13}{33}\)\(\Rightarrow\frac{13}{33}=\frac{143}{363}\)
b)\(\frac{1212}{2727}=\frac{12.101}{27.101}=\frac{12}{27}\Rightarrow\frac{12}{27}=\frac{1212}{2727}\)
Ta có công thức tổng quát:\(\frac{abab}{bcbc}=\frac{ab}{bc}\)