\(\left(-2\right)\times-\frac{38}{21}\times-\frac{7}{4}\times\left(-\frac{3}{8}\right)\)

\(=\)\(\left(-2\times-\frac{38}{21}\right)\times\left(-\frac{7}{4}\times-\frac{3}{8}\right)\)

\(=\)\(\frac{76}{21}\times\frac{21}{32}\)

\(=\)\(\frac{76}{32}\)

\(=\)\(\frac{19}{8}\)

\(\left(-\frac{2}{3}+\frac{3}{7}\right)\div\frac{4}{5}+\left(-\frac{1}{3}+\frac{4}{7}\right)\div\frac{4}{5}\)

\(=\)\(-\frac{5}{21}\div\frac{4}{5}+\frac{5}{21}\div\frac{4}{5}\)

\(=\)\(-\frac{5}{21}\times\frac{5}{4}+\frac{5}{21}\times\frac{5}{4}\)

\(=\)\(\frac{5}{4}\times\left(-\frac{5}{21}+\frac{5}{21}\right)\)

\(=\)\(\frac{5}{4}\times0\)

\(=\)\(0\)

là ( -187 / 70 ) nha

\(\frac{3}{7}+\left(-\frac{5}{2}\right)+\left(-\frac{3}{5}\right)\)

\(=\)\(\frac{30}{70}+\left(-\frac{175}{70}\right)+\left(-\frac{42}{70}\right)\)

\(=\)\(-\frac{187}{70}\)

nnnnnnnn

ỐI RỒI ỚI

Mình làm hơi chậm ạ :

\(Q=\frac{0,4-\frac{2}{9}+\frac{2}{11}}{1,4+\frac{7}{9}+\frac{7}{11}}-\frac{\frac{1}{3}-0,25+\frac{1}{5}}{1\frac{1}{6}-0,875+0,7}\)

\(\Rightarrow Q=\frac{\frac{2}{5}-\frac{2}{9}+\frac{2}{11}}{\frac{7}{5}+\frac{7}{9}+\frac{7}{11}}-\frac{\frac{2}{3}-\frac{2}{8}+\frac{2}{10}}{\frac{7}{6}-\frac{7}{8}+\frac{7}{10}}\)

\(\Rightarrow Q=\frac{2.\left(\frac{1}{5}-\frac{1}{9}+\frac{1}{11}\right)}{7.\left(\frac{1}{5}+\frac{1}{9}+\frac{1}{11}\right)}-\frac{2.\left(\frac{1}{3}-\frac{1}{8}+\frac{1}{10}\right)}{7.\left(\frac{1}{6}-\frac{1}{8}+\frac{1}{10}\right)}\)

\(\Rightarrow Q=\frac{2}{7}-\frac{2}{7}=0\)

\(\left(\frac{-3}{4}+\frac{2}{5}\right):\frac{3}{7}+\left(\frac{3}{5}+\frac{-1}{4}\right):\frac{3}{7}\)

\(=\frac{3}{7}:\left(\frac{-3}{4}+\frac{2}{5}\right)+\left(\frac{3}{5}+\frac{-1}{4}\right)\)

\(=\frac{3}{7}:\left(\frac{-15}{20}+\frac{8}{20}\right)+\left(\frac{12}{20}+\frac{-5}{20}\right)\)

\(=\frac{3}{7}:\left(\frac{-7}{20}+\frac{7}{20}\right)\)

\(=\frac{3}{7}:\frac{-1}{20}=\frac{3}{7}.\frac{20}{-1}=\frac{60}{-7}=\frac{-60}{7}\)

B nha bn

Đáp án B. Đồng vị nha

7³ x 5⁸ = 32¹¹

\(7^3x5^8=>=343x687,5=235812,5\)

CHúc bạn THÀNH Công !! 

!!