\(\dfrac{0,4-\dfrac{2}{9}+\dfrac{2}{11}}{1,4-\dfrac{7}{9}+\dfrac{7}{11}}-\dfrac{\dfrac{1}{3}-0,25+\dfrac{1}{5}}{1\dfrac{1}{6}-0,875+0,7}\\ =\dfrac{2\left(0,2-\dfrac{1}{9}+\dfrac{1}{11}\right)}{7\left(0,2-\dfrac{1}{9}+\dfrac{1}{11}\right)}-\dfrac{2\left(\dfrac{1}{6}-0,125+0,1\right)}{7\left(\dfrac{1}{6}-0,125+0,1\right)}\\ =\dfrac{2}{7}-\dfrac{2}{7}\\ =0\)

Bài 1 : 

\(=\dfrac{2}{11}+\dfrac{4}{11}-\dfrac{6}{11}-\dfrac{3}{8}-\dfrac{5}{8}=0-1=-1\)

Bài 2 : 

\(\Rightarrow3+x=8\Leftrightarrow x=5\)

Bài 3 : 

\(\Leftrightarrow x-\dfrac{5}{11}=\dfrac{5}{4}\Leftrightarrow x=\dfrac{35}{44}\)

Bài 4 : 

Trong 2 ngày An đọc được số quyên phần quyên sách 

\(\dfrac{1}{11}+\dfrac{8}{11}=\dfrac{9}{11}\)( quyển sách ) 

đs : 9/11 quyển sách 

a: \(=\left(\dfrac{11}{17}+\dfrac{6}{17}\right)+\left(-\dfrac{5}{13}-\dfrac{8}{13}\right)+\dfrac{11}{25}\)

=11/25+1-1=11/25

b: \(=\sqrt{36\cdot\dfrac{1}{4}}+11=9+11=20\)

c: \(=\left(0.25\right)^8\cdot4^8=\left(0.25\cdot4\right)^8=1\)

d: \(=2.8\left(-6.5-3.5\right)=-10\cdot2.8=-28\)

`(5/6 -x+7/12) : ( 11/24 -1/8)=11/36`

`=>(5/6 -x+7/12) : (11/24 - 3/24)=11/36`

`=>(5/6 -x+7/12) : 8=11/36`

`=>5/6 -x+7/12=11/36 xx 8`

`=>5/6 -x+7/12=22/9`

`=> x+7/12=5/6-22/9`

`=> x+7/12=-29/18`

`=>x=-29/18 -7/12`

`=>x=-79/36`

79/36 nhé

\(\left(0.25\right)^{10}.4^{10}+\sqrt{5^2-3^2}\)
\(=0.4^{10}+\sqrt{25-9}\)
\(=0+\sqrt{16}=0+4=4\)

\(\dfrac{5}{20}+\dfrac{18}{11}-25\%-\left(\dfrac{18}{11}-\dfrac{4}{9}\right)\)
\(=\dfrac{5}{20}+\dfrac{18}{11}-\dfrac{1}{4}-\dfrac{18}{11}+\dfrac{4}{9}\)
\(=\left(\dfrac{5}{20}-\dfrac{1}{4}\right)+\left(\dfrac{18}{11}-\dfrac{18}{11}\right)+\dfrac{4}{9}\)
\(=0+0+\dfrac{4}{9}=\dfrac{4}{9}\)

    (0,25)¹⁰.4¹⁰ + \(\sqrt{5^2-3^2}\)

=   (0,25 .4)¹⁰ + \(\sqrt{25-9}\)

= 1¹⁰ + \(\sqrt{16}\)

= 1 + 4 

= 5

\(\dfrac{5}{20}\) + \(\dfrac{18}{11}\) - 25% - ( \(\dfrac{18}{11}\) - \(\dfrac{4}{9}\))

= 25% +  \(\dfrac{18}{11}\) - 25% - \(\dfrac{18}{11}\) + \(\dfrac{4}{9}\)

= ( 25% - 25%)  + ( \(\dfrac{18}{11}\) - \(\dfrac{18}{11}\)) + \(\dfrac{4}{9}\)

= 0  + 0 + \(\dfrac{4}{9}\)

= \(\dfrac{4}{9}\)

\(\dfrac{6:\dfrac{3}{5}-1\dfrac{1}{6}x\dfrac{6}{7}}{\dfrac{4}{5}x\dfrac{10}{11}+5\dfrac{2}{12}}=\left(10-x\right):\left(\dfrac{8}{11}x+\dfrac{31}{6}\right)\)

\(\dfrac{10-\dfrac{7}{6}\cdot x\cdot\dfrac{6}{7}}{\dfrac{8}{11}\cdot x+\dfrac{31}{6}}=\dfrac{10-1\cdot x}{\dfrac{8}{11}\cdot x+\dfrac{31}{6}}=\dfrac{10-\dfrac{11}{11}\cdot x}{\dfrac{8}{11}\cdot x+\dfrac{31}{6}}=\dfrac{10-\dfrac{3}{11}\cdot x}{\dfrac{31}{6}}=>10-\dfrac{3}{11}\cdot x=\dfrac{31}{6} =>\dfrac{3}{11}\cdot x=10-\dfrac{31}{6}=\dfrac{29}{6}=>x=\dfrac{29}{6}:\dfrac{3}{11}=\dfrac{319}{18}\)

\(\dfrac{21}{24}\cdot\dfrac{2}{11}:\dfrac{9}{8}=\dfrac{21}{24}\cdot\dfrac{2}{11}\cdot\dfrac{8}{9}=\dfrac{16}{99}\)

\(\dfrac{17}{9}\cdot\dfrac{5}{6}:\dfrac{12}{13}=\dfrac{17}{9}\cdot\dfrac{5}{6}\cdot\dfrac{13}{12}=\dfrac{1105}{648}\)

a)\(\dfrac{14}{99}\)

b)\(\dfrac{1105}{648}\)

\(\dfrac{16}{99};\dfrac{1105}{648}\)

a: \(=\dfrac{-6}{11}:\dfrac{3\cdot11}{4\cdot5}=\dfrac{-6}{11}\cdot\dfrac{20}{33}=\dfrac{-2}{11}\cdot\dfrac{20}{11}=\dfrac{-40}{121}\)

b: \(=\dfrac{7}{12}+\dfrac{5}{72}-\dfrac{11}{36}=\dfrac{42}{72}+\dfrac{5}{72}-\dfrac{22}{72}=\dfrac{25}{72}\)

c: \(=\dfrac{13}{10}:\dfrac{-5}{13}=\dfrac{-169}{50}\)