Verified answer

Ответ:

1) [tex](\frac{27}{28} -\frac{5}{9} )-(-\frac{1}{28}+8\frac{4}{9} )=\frac{103}{252} -(\frac{1}{28}+\frac{76}{9})=\frac{103}{252}-\frac{2119}{252}=-8[/tex]

2) [tex]-(-\frac{20}{27}+\frac{3}{8})+(-\frac{45}{8}+\frac{115}{27})=-(-\frac{79}{216})+(-\frac{45}{8}+\frac{115}{27})=\frac{79}{216}+(\frac{295}{216})=\frac{79}{216}-\frac{295}{216}=-1[/tex]

3)[tex](10,8-49\frac{2}{7})-(-9,2+3\frac{5}{7})=(\frac{54}{5}-\frac{345}{7})-(-\frac{46}{5}+\frac{26}{7})=(-\frac{1347}{35})-(-\frac{192}{35})=-\frac{1347}{35}+\frac{192}{35}=-33[/tex]

4) [tex]-(81,3-3\frac{11}{16})-(9,9-11\frac{5}{16})=-(\frac{813}{10}-\frac{59}{16})-(\frac{99}{10}-\frac{181}{16})=-\frac{6209}{80}-(-\frac{113}{80})=-\frac{6209}{80}+\frac{113}{80}=-\frac{381}{5}[/tex]

Альтернативной формой [tex]-\frac{381}{5}[/tex] являются [tex]-76\frac{1}{5}[/tex] и [tex]-76,2[/tex]

Тут все расписано верно. Удачи.