a: =>x*2/15=2/7

=>x=2/7:2/15=2/7*15/2=15/7

b: x=3:7/5=15/7

c: x=-1/2:4/9=-1/2*9/4=-9/8

d: x=-8/3:3/8=-64/9

g: =>4/11x=2/5+1/3=6/15+5/15=11/15

=>x=11/15:4/11=121/60

l: =>1/4:x=1-3/2=-1/2

=>x=-1/4:1/2=-1/4*2=-1/2

k: =>x:7=-1/3+5/2=-2/6+15/6=13/6

=>x=91/6

\(x-40\%x=3,6\)

\(\Rightarrow100\%x-40\%x=3,6\)

\(\Rightarrow60\%x=3,6\)

\(\Rightarrow\frac{60}{100}x=3,6\)

\(\Rightarrow x=6\)

\(3\frac{2}{7}x-\frac{1}{3}=-2\frac{3}{4}\)

\(\Rightarrow\frac{23}{7}x-\frac{1}{3}=-\frac{11}{4}\)

\(\Rightarrow\frac{23}{7}x=-\frac{33}{12}+\frac{4}{12}\)

\(\Rightarrow\frac{23}{7}x=\frac{29}{12}\)

\(\Rightarrow x=\frac{29}{12}:\frac{23}{7}=\frac{203}{276}\)

\(-\frac{4}{7}+\frac{5}{7}:x=\frac{1}{6}\)

\(\Rightarrow\frac{5}{7}:x=\frac{1}{6}+\frac{4}{7}\)

\(\Rightarrow\frac{5}{7}:x=\frac{7}{42}+\frac{24}{42}\)

\(\Rightarrow\frac{5}{7}:x=\frac{33}{42}\)

\(\Rightarrow x=\frac{5}{7}:\frac{33}{42}\)

\(\Rightarrow x=\frac{5}{7}.\frac{6.7}{33}=\frac{30}{33}\)

a) 2/7 X x = 2/3 

X = 2/3 : 2/7 

X = 7/3

b) 2/5 : x = 1/3

X =  2/5 : 1/3

X = 6/5

c) x : 7/11 = 22

X = 22 x 7/11

X = 14

d) 1/2 : x = 5

X = 1/2 : 5

X = 1/10

a) x = 2/3 : 2/7

x = 7/3

vậy x =...

b) x = 2/5 : 1/3

x = 6/5

vậy x =..

c) x = 22 x 7/11

x = 14

vậy x =...

d) x = 1/2 : 5

x = 1/10

vậy x =...

a) \(\dfrac{2}{7}\times x=\dfrac{2}{3}\)

            \(x=\dfrac{2}{3}\div\dfrac{2}{7}\)

           \(x=\dfrac{7}{3}\)

b) \(\dfrac{2}{5}:x=\dfrac{1}{3}\)

          \(x=\dfrac{2}{5}:\dfrac{1}{3}\)

          \(x=\dfrac{6}{5}\)

c) \(x:\dfrac{7}{11}=22\)

    \(x=22\times\dfrac{7}{11}\)

    \(x=\dfrac{154}{11}\)

   \(x=14\)

d) \(\dfrac{1}{2}:x=5\)

          \(x=\dfrac{1}{2}:5\)

          \(x=\dfrac{1}{10}\)

đây đâu phải toán 6 đâu

toán 6 mà má

\(A=\dfrac{-19}{9}.\dfrac{1}{2}-\dfrac{4}{11}.\dfrac{-11}{9}+\left(-\dfrac{2}{3}\right)=-\dfrac{23}{18}\)

\(B=\left(-\dfrac{15}{6}\right):\dfrac{-1}{2}+\dfrac{7}{-12}-\dfrac{1}{3}.\dfrac{-11}{2}=\dfrac{25}{4}\)

\(C=\dfrac{3}{4}.\left(-8\right)-\dfrac{1}{3}.\dfrac{-7}{2}-\dfrac{5}{18}=-\dfrac{46}{9}\)

\(A=\dfrac{-19}{18}+\dfrac{4}{9}-\dfrac{2}{3}=\dfrac{-19}{18}+\dfrac{8}{18}-\dfrac{12}{18}=\dfrac{-23}{18}\)

\(B=\dfrac{-5}{2}\cdot\dfrac{-2}{1}-\dfrac{7}{12}+\dfrac{11}{6}=\dfrac{5\cdot12-7+22}{12}=\dfrac{75}{12}=\dfrac{25}{4}\)

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

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

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

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

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

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

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

\(=\frac{7}{22}:\frac{7}{11}=\frac{7}{22}.\frac{11}{7}=\frac{1}{2}\)

chúc bn học tốt!

a) \(\frac{3}{5}.x-\frac{1}{5}=\frac{4}{5}\)

\(\Leftrightarrow\frac{3}{5}.x=\frac{4}{5}+\frac{1}{5}\)

\(\Leftrightarrow\frac{3}{5}.x=1\)

\(\Leftrightarrow x=1:\frac{3}{5}\)

\(\Leftrightarrow x=\frac{5}{3}\)

Vậy : \(x=\frac{5}{3}\)

b) \(\frac{4}{7}+\frac{5}{7}:x=1\)

\(\Leftrightarrow\frac{5}{7}:x=1-\frac{4}{7}\)

\(\Leftrightarrow\frac{5}{7}:x=\frac{3}{7}\)

\(\Leftrightarrow x=\frac{5}{7}:\frac{3}{7}\)

\(\Leftrightarrow x=\frac{5}{3}\)

Vậy : \(x=\frac{5}{3}\)

c) \(-\frac{12}{7}.\left(\frac{3}{4}-x\right).\frac{1}{4}=-1\)

\(\Leftrightarrow\frac{-12.1}{7.4}.\left(\frac{3}{4}-x\right)=-1\)

\(\Leftrightarrow-\frac{3}{7}.\left(\frac{3}{4}-x\right)=-1\)

\(\Leftrightarrow\frac{3}{4}-x=-1:\left(-\frac{3}{7}\right)\)

\(\Leftrightarrow\frac{3}{4}-x=\frac{7}{3}\)

\(\Leftrightarrow x=\frac{3}{4}-\frac{7}{3}=-\frac{19}{12}\)

Vậy : \(x=-\frac{19}{12}\)

d) \(x:\frac{17}{8}=-\frac{2}{5}.-\frac{9}{17}+3\)

\(\Leftrightarrow x:\frac{17}{8}=\frac{273}{85}\)

\(\Leftrightarrow x=\frac{273}{85}.\frac{17}{8}\)

\(\Leftrightarrow x=\frac{273}{40}\)

Vậy : \(x=\frac{273}{40}\)

\(\)