第109页

信息发布者:
$\frac{1}{4}$ 
$\frac{9}{7}$ 
$\frac{11}{30}$
$\frac{1}{2}$ 
$\frac{1}{8}$
$\frac{2}{9}$
$=(\frac {4}{9}+\frac {5}{9})+\frac {6}{7}$
= $\frac{13}{7}$
$=\frac {3}{4}-\frac {1}{2}$
= $\frac{1}{4}$
$=\frac {5}{36}$
= $\frac{1}{6}$
$=(\frac {2}{3}+\frac {1}{3})-(\frac {3}{8}+\frac {5}{8}) $
$=0 $
$=(\frac {13}{7}-\frac {6}{7})-(\frac {4}{5}+\frac {1}{5}) $
$=0 $
解:4x=31.2
$x=7.8$
解:12x=48
$x=4$
解:8x=56
$x=7$
1,2,3,4,6,12 
1,2,3,6,9,18 
1,2,3,6 

0,6