[tex]find\ LCM(9;\ 3;\ 18)\\9=\fbox3\cdot\fbox3\\3=\fbox3\\18=2\cdot\fbox3\cdot\fbox3\\\\LCM(9;\ 3;\ 18)=\fbox3\cdot\fbox3\cdot2=\boxed{\boxed{18}}\\\\\frac{1}{9}=\frac{1\cdot2}{9\cdot2}=\frac{2}{18};\ \frac{2}{3}=\frac{2\cdot6}{3\cdot6}=\frac{12}{18};\\\\\frac{1}{9}+\frac{2}{3}+\frac{5}{18}=\frac{2}{18}+\frac{12}{18}+\frac{5}{18}=\frac{2+12+5}{18}=\frac{19}{18}=\frac{18+1}{18}=\frac{18}{18}+\frac{1}{18}=\boxed{1\frac{1}{18}}[/tex]
