Ta có :

\(1,4.\dfrac{15}{49}-\left(20\%+\dfrac{2}{3}\right):\dfrac{11}{5}\)

\(=\dfrac{14}{10}.\dfrac{15}{49}-\left(\dfrac{20}{100}+\dfrac{2}{3}\right).\dfrac{5}{11}\)

\(=\dfrac{7}{5}.\dfrac{15}{49}-\left(\dfrac{1}{5}+\dfrac{2}{3}\right).\dfrac{5}{11}\)

\(=\dfrac{3}{7}-\dfrac{13}{15}.\dfrac{5}{11}\)

\(=\dfrac{3}{7}-\dfrac{13}{33}=\dfrac{8}{231}\)

~ Học tốt ~

\(1.4\times\dfrac{15}{49}-\left(20\%+\dfrac{2}{3}\right):\dfrac{11}{5}\)

\(=\dfrac{7}{5}\times\dfrac{15}{49}-\left(\dfrac{1}{5}+\dfrac{2}{3}\right):\dfrac{11}{5}\)

\(=\dfrac{3}{7}-\dfrac{13}{15}:\dfrac{11}{15}\)

\(=\dfrac{3}{7}-\dfrac{11}{5}=\dfrac{13}{33}\)

bạn trg nào

\(\frac{-7}{12}+\frac{11}{8}-\frac{5}{9}\)

\(=\frac{-42}{72}+\frac{99}{72}+\frac{-40}{72}\)

\(=\frac{17}{72}\)

sorry, i can't anwer your question.

A=-1/10

B câu b có và 1/5 là sao pn

\(\frac{1}{4}.\frac{15}{49}-\left(\frac{4}{5}+\frac{2}{3}\right)\div3\frac{2}{3}\)

\(=\frac{15}{196}-\left(\frac{12}{15}+\frac{10}{15}\right)\div\frac{11}{3}\)

\(=\frac{15}{196}-\left(\frac{12}{15}+\frac{10}{15}\right).\frac{3}{11}\)

\(=\frac{15}{196}-\frac{22}{15}.\frac{3}{11}\)

\(=\frac{15}{196}-\frac{2}{5}.\frac{1}{1}\)

\(=\frac{15}{196}-\frac{2}{5}\)

\(=\frac{75}{980}-\frac{392}{980}=\frac{-317}{980}\)

\(\frac{1}{4}\cdot\frac{15}{49}-\left(\frac{4}{5}+\frac{2}{3}\right):3\frac{2}{3}\)

\(=\frac{15}{196}-\frac{22}{15}\cdot\frac{3}{11}\)

\(=\frac{15}{196}-\frac{2}{5}\)

\(=-\frac{317}{980}\)

Giải:

B=1,4 .15/49 - (4/5+2/3) :2 1/5

B=7/5.15/49 - 22/15 : 11/5

B=3/7 - 2/3

B=-5/21

Chúc bạn học tốt!

2021+ 20% + 4/5

= 2021+(1/5 + 4/5)

=2021 + 1 

= 2022

giúp mình nhanh nhé

\(\frac{7}{9}\cdot\frac{8}{11}+\frac{7}{9}\cdot\frac{3}{11}-\frac{45}{19}\)

\(=\frac{7}{9}\left[\frac{8}{11}+\frac{3}{11}\right]-\frac{45}{19}\)

\(=\frac{7}{9}\cdot1-\frac{45}{19}=-\frac{272}{171}\)

\(1,4\cdot\frac{15}{49}-\left[20\%+\frac{2}{3}\right]:\frac{11}{5}\)

\(=\frac{14}{10}\cdot\frac{15}{49}-\left[\frac{20}{100}+\frac{2}{3}\right]\cdot\frac{5}{11}\)

\(=\frac{7}{5}\cdot\frac{15}{49}-\left[\frac{1}{5}+\frac{2}{3}\right]\cdot\frac{5}{11}\)

\(=\frac{1}{1}\cdot\frac{3}{7}-\frac{13}{15}\cdot\frac{5}{11}\)

\(=\frac{3}{7}-\frac{13}{3}\cdot\frac{1}{11}\)

\(=\frac{3}{7}-\frac{13}{33}=\frac{8}{231}\)

\(-\frac{7}{6}-x=\frac{1}{6}\)

\(\Rightarrow x=-\frac{7}{6}-\frac{1}{6}\)

\(\Rightarrow x=-\frac{4}{3}\)

 \(30\%x=-\frac{6}{5}\)

\(\Rightarrow\frac{30}{100}x=-\frac{6}{5}\)

\(\Rightarrow\frac{3}{10}x=-\frac{6}{5}\Leftrightarrow x=-4\)

Làm nốt hai bài còn lại