a, \(\dfrac{62}{7}.x=\dfrac{29}{90}.\dfrac{3}{56}\)

\(\dfrac{62}{7}.x=\dfrac{29}{1680}\)

\(x=\dfrac{29}{1680}:\dfrac{62}{7}\)

\(x=\dfrac{29}{14880}\)

b, \(\dfrac{1}{5}:x=\dfrac{1}{5}-\dfrac{1}{7}\)

\(\dfrac{1}{5}:x=\dfrac{2}{35}\)

\(x=\dfrac{1}{5}:\dfrac{2}{35}\)

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

c, \(\left(x+\dfrac{1}{4}-\dfrac{1}{3}\right):\left(2+\dfrac{1}{6}-\dfrac{1}{4}\right)=\dfrac{7}{46}\)

\(\left(x+\dfrac{1}{4}-\dfrac{1}{3}\right):\left(\dfrac{13}{6}-\dfrac{1}{4}\right)=\dfrac{7}{46}\)

\(\left(x+\dfrac{1}{4}-\dfrac{1}{3}\right):\dfrac{23}{12}=\dfrac{7}{46}\)

\(\left(x+\dfrac{-1}{12}\right):\dfrac{23}{12}=\dfrac{7}{46}\)

\(\left(x+\dfrac{-1}{12}\right)=\dfrac{7}{46}.\dfrac{23}{12}\)

\(x+\dfrac{-1}{12}=\dfrac{7}{24}\)

\(x=\dfrac{7}{24}-\dfrac{-1}{12}\)

\(x=\dfrac{3}{8}\)

a) \(\frac{62}{7}.x=\frac{29}{9}\)

\(\Rightarrow x=\frac{29}{9}:\frac{62}{7}=\frac{29}{9}.\frac{7}{62}=\frac{203}{468}\)

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

\(\Rightarrow\frac{1}{5}:x=\frac{2}{35}\)

\(\Rightarrow x=\frac{1}{5}:\frac{2}{35}=\frac{1}{5}.\frac{35}{2}=\frac{7}{2}\)

\(a,\frac{62}{7}:x=\frac{29}{9}:\frac{3}{56}\)

\(\frac{62}{7}:x=\frac{1624}{27}\)

\(x=\frac{62}{7}:\frac{1624}{27}=\frac{837}{5684}\)

\(b,\frac{1}{5}:x=\frac{1}{5}-\frac{1}{7}\)

\(\frac{1}{5}:x=\frac{2}{35}\)

\(x=\frac{1}{5}:\frac{2}{35}=\frac{7}{2}\)

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

\(\frac{2}{3}.x=\frac{1}{7}+\frac{4}{7}=\frac{5}{7}\)

\(x=\frac{5}{7}:\frac{2}{3}=\frac{15}{14}\)

\(d,\frac{2}{7}-\frac{8}{9}.x=\frac{2}{3}\)

\(\frac{8}{9}.x=\frac{2}{7}-\frac{2}{3}=-\frac{8}{21}\)

\(x=-\frac{8}{21}:\frac{8}{9}=-\frac{3}{7}\)

\(e,\frac{4}{7}+\frac{5}{9}:x=\frac{1}{5}\)

\(\frac{5}{9}:x=\frac{1}{5}-\frac{4}{7}=-\frac{13}{35}\)

\(x=\frac{5}{9}:-\frac{13}{35}=\frac{175}{117}\)

\(i,\frac{2}{5}-\frac{2}{5}.x=\frac{2}{5}\)

\(\frac{2}{5}.\left(1-x\right)=\frac{2}{5}\)

\(1-x=\frac{2}{5}:\frac{2}{5}=1\)

\(x=1-1=0\)

\(g,\frac{2}{3}+\frac{1}{3}:x=-1\)

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

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

học tốt nha

a, \(\frac{62}{7}.x=\frac{29}{9}.\frac{56}{3}=\frac{1624}{27}\)

\(x=\frac{1624}{27}:\frac{62}{7}=\frac{1624}{27}.\frac{7}{62}=6\frac{662}{837}\)

b, \(\frac{1}{50}:x=\frac{7}{35}+\frac{5}{35}=\frac{12}{35}\)

\(x=\frac{12}{35}.\frac{1}{50}=\frac{6}{875}\)

\(\frac{62}{7}.x=\frac{29}{9}:\frac{3}{56}\Leftrightarrow\frac{62}{7}.x=\frac{1624}{27};x=\frac{5684}{837}\)

\(a)\frac{62}{7}\cdot x=\frac{29}{9}\div\frac{3}{56}\)

\(\Rightarrow\frac{62}{7}\cdot x=\frac{29}{9}\cdot\frac{56}{3}\)

\(\Rightarrow\frac{62}{7}\cdot x=\frac{1624}{27}\)

\(\Rightarrow x=\frac{1624}{27}\div\frac{62}{7}\)

\(\Rightarrow x=\frac{1624}{27}\cdot\frac{7}{62}\)

\(\Rightarrow x=\frac{11368}{1674}=\frac{5684}{837}\)

Rút gọn thử đi

Giải:

a) \(2\dfrac{17}{20}-1\dfrac{15}{11}+6\dfrac{9}{20}:3\)

\(=\dfrac{57}{20}-\dfrac{26}{11}+\dfrac{129}{20}:3\) 

\(=\dfrac{107}{220}+\dfrac{43}{20}\)

\(=\dfrac{29}{11}\)

b) \(4\dfrac{3}{7}:\left(\dfrac{7}{5}.4\dfrac{3}{7}\right)\) 

\(=\dfrac{31}{7}:\left(\dfrac{7}{5}.\dfrac{31}{7}\right)\) 

\(=\dfrac{31}{7}:\dfrac{31}{5}\) 

\(=\dfrac{5}{7}\) 

c) \(\left(3\dfrac{2}{9}.\dfrac{15}{23}.1\dfrac{7}{29}\right):\dfrac{5}{23}\) 

\(=\left(\dfrac{29}{9}.\dfrac{15}{23}.\dfrac{36}{29}\right):\dfrac{5}{23}\) 

\(=\dfrac{60}{23}:\dfrac{5}{23}\) 

\(=12\)

a: \(\Leftrightarrow x\cdot\dfrac{62}{7}=\dfrac{29}{9}\cdot\dfrac{56}{3}=\dfrac{1624}{27}\)

hay \(x=\dfrac{1624}{27}:\dfrac{62}{7}=\dfrac{5684}{837}\)

b: \(\Leftrightarrow\dfrac{1}{5}:x=\dfrac{12}{35}\)

nên \(x=\dfrac{1}{5}:\dfrac{12}{35}=\dfrac{1}{5}\cdot\dfrac{35}{12}=\dfrac{7}{12}\)

c: \(\Leftrightarrow\left|2x+\dfrac{1}{3}\right|=\dfrac{30-7}{42}=\dfrac{23}{42}\)

=>2x+1/3=23/42 hoặc 2x+1/3=-23/42

=>2x=3/14 hoặc 2x=-37/42

=>x=3/28 hoặc x=-37/84

Bài 1:

a) x + \(\frac{1}{9}\) - \(\frac{3}{5}\) = \(\frac{3}{6}\)                                                                                     b) \(\frac{3}{4}\) - x + \(\frac{6}{11}\) = \(\frac{5}{6}\)

    x + \(\frac{1}{9}\)       = \(\frac{3}{6}\) + \(\frac{3}{5}\)                                                                                   \(\frac{3}{4}\) - x         = \(\frac{5}{6}\) - \(\frac{6}{11}\)

    x + \(\frac{1}{9}\)       = \(\frac{11}{10}\)                                                                                         \(\frac{3}{4}\) - x         = \(\frac{19}{66}\)

    x              = \(\frac{11}{10}\) - \(\frac{1}{9}\)                                                                                     x             = \(\frac{19}{66}\) + \(\frac{3}{4}\)

    x              = \(\frac{89}{90}\)                                                                                            x             = \(\frac{137}{132}\)

Bài 2

a) x : 13/16 = 5/8                                                               b)x - 14/28 = 6/9 + 8/25

   x               = 5/8 * 13/16                                                    x - 14/28 = 74/75

   x               = 65/128                                                          x              = 74/75 + 14/28

                                                                                            x               = 223/150

Bài 3

a)62/7 * x = 29/9 : 3/56                                      b)1/5 : x = 1/5 + 1/7                         

   62/7 * x = 1624/27                                              1/5 : x = 12/35

   x           = 1624/27 : 62/7                                            x  = 12/35 * 1/5

  x            = 5684/637                                                    x  = 12/175