A=0

B=8

a) \(\frac{-5}{9}+\frac{5}{9}:\left(1\frac{2}{3}-2\frac{1}{12}\right)\)

\(=\frac{-5}{9}+\frac{5}{9}:\left(\frac{5}{3}-\frac{25}{12}\right)\)

\(=\frac{-5}{9}+\frac{5}{9}:\frac{\left(-5\right)}{12}\)

\(=\frac{-5}{9}+\frac{5}{9}.\frac{12}{\left(-5\right)}\)

\(=\frac{-5}{9}.\left(1+\frac{12}{5}\right)\)

\(=\frac{-5}{9}.\frac{17}{5}\)

\(=\frac{-17}{9}\)

b) \(\frac{-7}{25}.\frac{11}{13}+\frac{-7}{25}.\frac{2}{13}-\frac{18}{25}\)

\(=\frac{-7}{25}.\left(\frac{11}{13}+\frac{2}{13}\right)-\frac{18}{25}\)

\(=\frac{-7}{25}-\frac{18}{25}\)

\(=-1\)

Chúc bn học tốt !!!

ổi câu a sao mk bấm mấy ra kq là 5/9

a)\(\dfrac{-5}{9}+\dfrac{5}{9}:\left(1\dfrac{2}{3}-2\dfrac{1}{12}\right)\)

\(=\dfrac{-5}{9}+\dfrac{5}{9}:\left(\dfrac{20}{12}-\dfrac{25}{12}\right)\)

\(=\dfrac{-5}{9}+\dfrac{5}{9}\cdot\dfrac{-12}{5}\)

\(=\dfrac{-5}{9}+\dfrac{-12}{9}\)

\(=\dfrac{-17}{9}\)

b) \(\dfrac{-7}{25}\cdot\dfrac{11}{13}+\dfrac{-7}{25}\cdot\dfrac{2}{13}-\dfrac{18}{25}\)

\(=\dfrac{-7}{25}\cdot\left(\dfrac{11}{13}+\dfrac{2}{13}\right)-\dfrac{18}{25}\)

\(=\dfrac{-7}{25}\cdot1-\dfrac{18}{25}\)

\(=\dfrac{-25}{25}\)

\(=-1\)

c) \(\left(\dfrac{5}{7}\cdot0,6-5:3\dfrac{1}{2}\right)\cdot\left(40\%-1,4\right)\cdot\left(-2\right)^3\)

\(=\left(\dfrac{3}{7}-\dfrac{10}{7}\right)\cdot\left(0,4-1,4\right)\cdot\left(-8\right)\)

\(=\left(-1\right)\cdot\left(-1\right)\cdot\left(-8\right)\)

\(=-8\)

Giải:

h) \(\left(-\dfrac{1}{2}\right)^2.13\dfrac{9}{11}-25\%.6\dfrac{2}{11}\)

\(=\dfrac{1}{4}.\dfrac{152}{11}-\dfrac{1}{4}.\dfrac{68}{11}\)

\(=\dfrac{1}{4}\left(\dfrac{152}{11}-\dfrac{68}{11}\right)\)

\(=\dfrac{1}{4}.\dfrac{84}{11}=\dfrac{21}{11}\)

Vậy ...

i) \(57\%+1\dfrac{2}{15}:\dfrac{68}{25}-2,82\)

\(=\dfrac{57}{100}+\dfrac{17}{15}:\dfrac{68}{25}-\dfrac{141}{50}\)

\(=\dfrac{57}{100}+\dfrac{2}{15}-\dfrac{141}{50}\)

\(=\dfrac{-127}{60}\)

Vậy ...

h. \(\left(-\dfrac{1}{2}\right)^2\times13\dfrac{9}{11}-25\%\times6\dfrac{2}{11}\)

= \(\dfrac{1}{4}\times\dfrac{150}{11}-\dfrac{1}{4}\times34\)

= \(\dfrac{75}{22}-\dfrac{17}{2}\)

= \(\dfrac{75}{22}-\dfrac{187}{22}\)

= \(-\dfrac{56}{11}\)

i. \(57\%+1\dfrac{2}{15}\div\dfrac{68}{25}-2,82\)

= \(\dfrac{57}{100}+\dfrac{17}{15}\div\dfrac{68}{25}-\dfrac{282}{100}\)

= \(\dfrac{57}{100}+\dfrac{17}{15}\times\dfrac{25}{68}-\dfrac{282}{100}\)

= \(\dfrac{57}{100}+\dfrac{5}{3}-\dfrac{282}{100}\)

=\(\dfrac{5}{3}-\left(\dfrac{57}{100}-\dfrac{282}{100}\right)\)

= \(\dfrac{5}{3}-\left(-\dfrac{215}{100}\right)\)

= \(\dfrac{5}{3}-\left(-\dfrac{43}{20}\right)\)

= \(\dfrac{5}{3}+\dfrac{43}{30}\)

= \(\dfrac{50}{30}+\dfrac{43}{30}\)

= \(\dfrac{31}{10}\)

mik làm được mỗi ý b thui : 

b ) \(\frac{169}{10}=16,9\)

mik nha

phần đầu bằng -6675/128

phần sau bằng 13 

bạn dùng máy tính là được mà

\(\frac{7}{-25}\) \(+\) \(\frac{-18}{25}\) \(+\) \(\frac{4}{23}\) \(+\) \(\frac{5}{7}\) \(+\) \(\frac{19}{23}\) \(+\) \(\frac{2}{14}\)

\(=\)\(\frac{6}{7}\)

= 6/7 bạn nhé ^^ 

Chúc bạn học tốt . Tích cho mink nhé <3

a: \(=\dfrac{-7}{25}\left(\dfrac{11}{13}+\dfrac{2}{13}\right)-\dfrac{18}{25}=\dfrac{-7}{25}-\dfrac{18}{25}=-1\)

c: \(=\dfrac{5}{7}\left(\dfrac{1}{3}-\dfrac{1}{4}-\dfrac{1}{12}\right)=0\)

c: \(=\dfrac{27}{5}\cdot\dfrac{30}{7}+\dfrac{40}{7}\cdot\dfrac{37}{5}\)

\(=\dfrac{27\cdot30+40\cdot37}{35}=\dfrac{458}{7}\)

d: \(=\dfrac{3}{4}-\dfrac{3}{2}+\dfrac{1}{2}\cdot\dfrac{12}{5}-\dfrac{1}{4}\)

\(=\dfrac{1}{2}-\dfrac{3}{2}+\dfrac{6}{5}=-1+\dfrac{6}{5}=\dfrac{1}{5}\)

a: =>2/3x=1/10+1/2=1/10+5/10=6/10=3/5

=>x=3/5:2/3=3/5x3/2=9/10

b: \(\Leftrightarrow x\cdot2.8-50=34\)

=>2,8x=84

=>x=30

c: \(\Leftrightarrow\dfrac{1}{6}x=\dfrac{5}{12}\)

hay x=5/2

d: \(\Leftrightarrow\left|2x-\dfrac{3}{4}\right|=\dfrac{17}{2}+\dfrac{7}{4}=\dfrac{41}{4}\)

=>2x-3/4=41/4 hoặc 2x-3/4=-41/4

=>2x=44/4=11 hoặc 2x=-19/2

=>x=11/2 hoặc x=-19/4

Dấu " / " là phân số nhé

a) 5/-4 . 16/25 + -5/4 . 9/25

= -5/4 . 16/25 + -5/4 . 9/25

= -5/4 . ( 16/25 + 9/25 )

= -5/4 . 1

= -5/4

b) 4 11/23 - 9/14 + 2 12/23 - 5/4

= 103/23 - 9/14 + 58/23 - 5/4

= 103/23 + 58/23 - 9/14 - 5/4

= 7 - 9/14 - 5/4

= 143/28

c) 2 13/27 - 7/15 + 3 14/27 - 8/15

= 67/27 - 7/15 + 95/27 - 8/15

= 67/27 + 95/27 - 7/15 - 8/15

= 6 - 7/15 - 8/15

= 5