[tex]a)\\\\2,5+( \frac{2}{3}-1,8* \frac{5}{6})*9=2,5+( \frac{2}{3}-\frac{\not{18}^3}{\not{10}^2}* \frac{\not{5}^1}{\not{6}^1})*9=2,5+( \frac{2}{3}- \frac{3}{2})*9=\\\\=2,5+( \frac{4}{6}- \frac{9} {6})*9=2\frac{5}{10}+(-\frac{5}{\not{6}^2})*\not{9}^3=2\frac{1}{2}- \frac{15}{2}= 2\frac{1}{2}- 7\frac{1 }{2}=-5\\\\b)\\\\16 :(5* \frac{1}{2}-4,5)=16 :( \frac{5}{2}-\frac{4 5}{10})=16 :( \frac{5}{2}-\frac{9}{2})=16:(-2)=-8\\\\c)\\\\\frac{2}{3}:(-0,2)+4\frac{2}{3}=\frac{2}{3}:(-\frac{ 2}{10})+4\frac{2}{3}=\frac{\not{2}^1}{3}*(-\frac{10}{ \not{2}^1})+4\frac{2}{3}=-\frac{10}{3}+4\frac{2}{3}=\\\\=-3\frac{1}{3}+4\frac{2}{3}= 1\frac{2}{3}[/tex]
[tex]d)\\\\ 4\frac{1}{5}-0,6*(-2)=4\frac{1}{5}-\frac{6}{10}*(-2)=4\frac{1}{5}+\frac{6}{\not{10}^5}*( \not{2}^1)=4\frac{1}{5}+\frac{6}{5}=4\frac{1}{5}+1\frac{1}{5}=5\frac{2}{5}\\\\ e)\\\\-3,5*\frac{1}{14}-2\frac{1}{2}=-\frac{35}{10}*\frac{1}{14}-2\frac{1}{2}=-\frac{\not{7}^1}{2}*\frac{1}{\not{14}^2}-2\frac{1}{2}=-\frac{1}{4}-2\frac{1}{2}=-\frac{1}{4}-2\frac{2}{4}=-2\frac{3}{4}[/tex]
[tex]f)\\\\5,5 :( 4\frac{3}{4}-8,5)=5,5 :( 4\frac{3}{4}-8\frac{ 5}{10})=5,5 :( 4\frac{3}{4}-8\frac{ 1}{2})=5,5 :( 4\frac{3}{4}-8\frac{2}{4})=\\\\=\frac{55}{10}:(-3\frac{3}{4})=\frac{11}{2}:(- \frac{15}{4})=\frac{11}{\not{2}^1}*(- \frac {\not{4}^2}{15} ) =-\frac{22}{15}=-1\frac{7}{15}\\\\g)\\\\ -(1,2*\frac{5}{12} -0,8)+0,8=-(\frac{\not{12}^1}{\not{10}^2}*\frac{\not{5}^1}{\not{12}^1} - \frac{8}{10})+ \frac{8}{10}=-(\frac{1}{2}-\frac{8}{10})+\frac{8}{10}=\\\\=-(\frac{5}{10}-\frac{8}{10})+\frac{8}{10}=-(-\frac{3}{10})+\frac{8}{10}=\frac{3}{10}+\frac{8}{10}=\frac{11}{10}[/tex]
