Chuyển các hỗn số 2 4/9 ; 1 2/13 ; 7 10/21 ; 6 6/13 ; 5 9/20 ; 9 23/54 ; 1 2 9 ; 2 1/ 8 thành phân số

\[2\frac{4}{9} = 2 + \frac{4}{9} = \frac{{18}}{9} + \frac{4}{9} = \frac{{22}}{9}\]

\[1\frac{2}{{13}} = 1 + \frac{2}{{13}} = \frac{{13}}{{13}} + \frac{2}{{13}} = \frac{{15}}{{13}}\]

\[7\frac{{10}}{{21}} = 7 + \frac{{10}}{{21}} = \frac{{147}}{{21}} + \frac{{10}}{{21}} = \frac{{157}}{{21}}\]

\[6\frac{6}{{13}} = 6 + \frac{6}{{13}} = \frac{{78}}{{13}} + \frac{6}{{13}} = \frac{{84}}{{13}}\]

\[5\frac{9}{{20}} = 5 + \frac{9}{{20}} = \frac{{100}}{{20}} + \frac{9}{{20}} = \frac{{109}}{{20}}\]

\[9\frac{{23}}{{54}} = 9 + \frac{{23}}{{54}} = \frac{{486}}{{54}} + \frac{{23}}{{54}} = \frac{{509}}{{54}}\]

\[1\frac{2}{9} = 1 + \frac{2}{9} = \frac{9}{9} + \frac{2}{9} = \frac{{11}}{9}\]

\[2\frac{1}{8} = 2 + \frac{1}{8} = \frac{{16}}{8} + \frac{1}{8} = \frac{{17}}{8}\]