[tex]23a)\\\\9:\frac{1}{3}-\frac{18}{5} *2\frac{1}{2}=9*\frac{3}{1}-\frac{\not{18}^9}{\not{5}^1} * \frac{\not{5}^1}{\not{2}^1}=27-9=18\\\\b)\\\\5\frac{1}{4}*(1\frac{1}{2}-\frac{2}{7})=\frac{21}{4}*(\frac{3}{2}-\frac{2}{7})=\frac{21}{4}*(\frac{21}{14}-\frac{4}{14})=\frac{21}{4}* \frac{17}{14}=\frac{357}{56}=\frac{51}{8}=6\frac{3}{8}\\\\c)\\\\\frac{5}{6}:10+1\frac{1}{3} *\frac{5}{16}=\frac{\not{5}^1}{6} *\frac{1}{\not{10}^2}+ \frac{\not{4}^1}{3} *\frac{5}{\not{16}^4}=\frac{1 }{12}+\frac{5}{12}=\frac{6}{12}=\frac{1}{2}[/tex]
[tex]d)\\\\ ( \frac{5}{6})^2:1\frac{1}{4}*3^2-\frac{3}{4}= \frac{25}{36} : \frac{5}{4}*9-\frac{3}{4}= \frac{\not{25}^5}{\not{36}^4}*\frac{4}{\not{5}^1}*\not{9}^1-\frac{3}{4}= \frac{20}{4}-\frac{3}{4}=\frac{17}{4}=4\frac{1}{4} \\\\e)\\\\\frac{2\frac{1}{3}-1\frac{1}{2}}{\frac{3}{5}:2-\frac{1}{4}}= \frac{2\frac{2}{6}-1\frac{3}{6}}{\frac{3}{5}*\frac{1}{2} -\frac{1}{4}}= \frac{1\frac{8}{6}-1\frac{3}{6}}{\frac{3}{10} -\frac{1}{4}}= \frac{ \frac{5}{6} }{\frac{6}{20} -\frac{5}{20}}= \frac{\frac{5}{6}}{\frac{1}{20}}=\frac{5}{6}:\frac{1}{20}=\\\\=\frac{5}{\not{6}^3}*\frac{\not{20}^{10}}{1}=\frac{50}{3}=16\frac{2}{3}[/tex]
