\(\dfrac{7}{22}:\dfrac{3}{11}+\dfrac{7}{22}:\dfrac{4}{11}=\dfrac{7}{22}.\dfrac{11}{3}+\dfrac{7}{22}.\dfrac{11}{4}=\dfrac{7}{22}\left(\dfrac{11}{3}+\dfrac{11}{4}\right)=\dfrac{7}{22}.\dfrac{77}{12}=\dfrac{49}{24}\)

7/11 chứ nhỉ ?

a, 7/12 - 3/4 . 5/6 

= 7/12 - 5/8

= 14/24- 15/24

= -1/24

b,( 2/1/3 + 1/3/4 ) . 12/13

= ( 6/3 + 7/3 ) . 12/13

= 13/3 . 12/13

=4

c, 12 : ( 3/4 -5/6 ) . 2

= 12 : ( -1/12 ) .2

= 12 . -12 . 2

= -228

d, 7/22 : 3/11 + 7/22 : 4/11 

= 7/22 . 11/3 + 7/22 . 11/4

= 7/22 . ( 11/3 + 11/4 )

....

tiếp theo bạn tự làm nhé!

Bài 1:

\(A=\left(\frac{-5}{11}+\frac{7}{22}-\frac{4}{33}-\frac{5}{44}\right):\left(38\frac{1}{122}-39\frac{7}{22}\right)\)

\(=\frac{-49}{132}:\left(-\frac{879}{671}\right)=\frac{2989}{105408}\)

Bài 2:

\(\frac{4}{5}-\left(\frac{-1}{8}\right)=\frac{7}{8}-x\)

<=>  \(\frac{7}{8}-x=\frac{27}{40}\)

<=>  \(x=\frac{7}{8}-\frac{27}{40}=\frac{1}{5}\)

Vậy...

bài 2 mình tính sai, sửa

.......

<=>  \(\frac{7}{8}-x=\frac{37}{40}\)

<=>  \(x=\frac{7}{8}-\frac{37}{40}=\frac{-1}{20}\)

Vậy....

\(\frac{7}{22}:\frac{3}{11}+\frac{7}{22}:\frac{4}{11}\)

\(=\frac{7}{22}:\left(\frac{3}{11}+\frac{4}{11}\right)\)

\(=\frac{7}{22}:\frac{7}{11}\)

\(=\frac{1}{2}\)

ti ck nha

\(\frac{7}{22}\) :  (\(\frac{3}{11}\)  +    \(\frac{4}{11}\) )

\(\frac{7}{22}\) :  \(\frac{7}{11}\)     =\(\frac{7}{22}\)  x   \(\frac{11}{7}\)    = 2

d: \(\dfrac{1}{27}:\left(-\dfrac{1}{3}\right)^2+75\%\cdot\left(-\dfrac{2^2}{3}\right)\)

\(=\dfrac{1}{27}:\dfrac{1}{9}+\dfrac{3}{4}\cdot\dfrac{-4}{3}\)

\(=\dfrac{1}{3}-1\)

\(=-\dfrac{2}{3}\)

a: Ta có: \(\left(-\frac57-\frac79+\frac{9}{11}-\frac{11}{13}\right)\cdot\left(3-\frac34\right)\)

\(=\left(-\frac{6435}{9009}-\frac{7007}{9009}+\frac{7371}{9009}-\frac{7623}{9009}\right)\cdot\frac94\)

\(=-\frac{13694}{9009}\cdot\frac94=\frac{-6847}{2}\cdot\frac{1}{1001}=\frac{-6847}{2002}\)

b: \(\left(\frac{10}{21}+\frac{14}{27}-\frac{6}{11}+\frac{22}{39}\right):\left(2-\frac23\right)\)

\(=\left(\frac{12870}{27027}+\frac{14014}{27027}-\frac{14742}{27027}+\frac{15246}{27027}\right):\frac43\)

\(=\frac{27388}{27027}\cdot\frac34=\frac{6847}{9009}\)

Ta có :\(\left(\frac{3}{2}-\frac{5}{11}-\frac{3}{13}\right).\left(2x-2\right)=\left(-\frac{3}{4}+\frac{5}{22}+\frac{3}{26}\right)\)

=> \(\left(\frac{3}{2}-\frac{5}{11}-\frac{3}{13}\right).\left(2x-2\right)=-\frac{1}{2}\left(\frac{3}{2}-\frac{5}{11}-\frac{3}{13}\right)\)

=> \(2x-2=-\frac{1}{2}\)

=> \(2x=\frac{3}{2}\)

=> \(x=\frac{3}{4}\)

cho mik xin bài giải với ạ