ДАЮ 20 БАЛЛОВ ,ПОМОГИТЕ!!!!!!найдите значение выражения (8,25*10\11-10)*(11 2\3:2...

Решите задачу:

$(8,25* \frac{10}{11} -10)*(11 \frac{2}{3}:2 \frac{2}{9}-6,15)+12,7:(-2 \frac{1}{2})=-4.83\\ 1) 8,25*\frac{10}{11}=8\frac{1}{4}*\frac{10}{11}= \frac{33}{4}*\frac{10}{11}=\frac{3*11*10}{4*11}=\frac{30}{4}=\frac{15}{2}\\ 2) \frac{15}{2}-10=\frac{15}{2}-\frac{20}{2}=-\frac{5}{2}\\ 3) 11 \frac{2}{3}:2\frac{2}{9}= \frac{35}{3}:\frac{20}{9}= \frac{35}{3}*\frac{9}{20}= \frac{5*7*3*3}{3*4*5}= \frac{21}{4}\\$
$4) \frac{21}{4}-6,15=\frac{21}{4}-6\frac{15}{100}=\frac{21}{4}-6\frac{3}{20}=\frac{21}{4}-\frac{123}{20}=\frac{125}{20}-\frac{123}{20}=\frac{2}{20}=\frac{1}{10}\\$
$5) -\frac{5}{2}*\frac{1}{10}= -\frac{5*1}{2*2*5}= -\frac{1}{4}\\ 6) 12,7:(-2 \frac{1}{2})=12\frac{7}{10}:(-2\frac{1}{2})=\frac{127}{10}:(-\frac{5}{2})=\\ \frac{127}{10}*(-\frac{2}{5})=-\frac{254}{50}=-\frac{508}{100}=-5.08\\ 7)\frac{1}{4}+(-5.08)=0.25+(-5.08)=-4.83$