( 1/2 - 1/3 + 1/4 ) : ( 1/6 - 1/x ) = 17,5

( 6/12 - 4/12 + 3/12 ) : ( 1/6 - 1/x) = 17,5

5/12 : ( 1/6 - 1/x ) = 17,5

  1/6 : 1/ x = 5/12 : 17,5

 1/6 : 1/ x  = 1/42

  1/x = 1/6 : 1/42 

  1/x  = 7

   1 : x = 7

   x = 1:7

  x= 1/7

\(\frac{1}{7}\)

Bài này là 1/7 bạn ạ!!!

\(\left[\frac{1}{2}-\frac{1}{3}+\frac{1}{4}\right]:\left[\frac{1}{6}-\frac{1}{x}\right]=17,5\)

\(\Rightarrow\frac{5}{12}:\left[\frac{1}{6}-\frac{1}{x}\right]=\frac{35}{2}\)

\(\Rightarrow\frac{1}{6}-\frac{1}{x}=\frac{5}{12}:\frac{35}{2}\)

\(\Rightarrow\frac{1}{6}-\frac{1}{x}=\frac{1}{42}\)

\(\Rightarrow\frac{1}{x}=\frac{1}{6}-\frac{1}{42}\)

\(\Rightarrow\frac{1}{x}=\frac{1}{7}\)

\(\Rightarrow x=1:\frac{1}{7}\)

\(\Rightarrow x=7\)

Học tốt # ^-<

help me

( 1/2 - 1/3 + 1/4 ) : ( 1/6 - 1/x ) = 17,5

( 6/12 - 4/12 + 3/12 ) : ( 1/6 - 1/x) = 17,5

5/12 : ( 1/6 - 1/x ) = 17,5

 1/6 : 1/ x = 5/12 : 17,5

  1/6 : 1/ x  = 1/42

  1/x = 1/6 : 1/42 

  1/x  = 7

    1 : x = 7

   x = 1:7

  x = 7

b) y/8 + 8y - 56,78 = 69,11 . 2

y/8+ 64y/8 = 138.22+ 56.78

65y/8 =195

65y= 1560

y= 24 

cho mik hỏi câu a đề có đúng ko vậy

câu a mình chép nhầm, thank bn

1/7 k nha mình chắc đúng luôn đó

\(\frac{6-4+3}{12}\): \(\frac{x-6}{6x}\)= 17,5 <=>\(\frac{\left(6-4+3\right).6x}{12\left(x-6\right)}\)= 17,5

 \(30x\)= 17,5.\(12\)(x - 6)

30x = 210x - 105 => 180x = 105 => x = \(\frac{105}{180}\)= \(\frac{21}{36}\)