a: \(x-\dfrac{10}{3}=\dfrac{7}{15}\cdot\dfrac{3}{5}\)

=>\(x-\dfrac{10}{3}=\dfrac{21}{75}=\dfrac{7}{25}\)

=>\(x=\dfrac{7}{25}+\dfrac{10}{3}=\dfrac{21+250}{75}=\dfrac{271}{75}\)

b: \(x+\dfrac{3}{22}=\dfrac{27}{121}\cdot\dfrac{9}{11}\)

=>\(x+\dfrac{3}{22}=\dfrac{243}{1331}\)

=>\(x=\dfrac{243}{1331}-\dfrac{3}{22}=\dfrac{123}{2662}\)

c: \(\dfrac{8}{23}\cdot\dfrac{46}{24}-x=\dfrac{1}{3}\)

=>\(\dfrac{8}{24}\cdot\dfrac{46}{23}-x=\dfrac{1}{3}\)

=>\(\dfrac{2}{3}-x=\dfrac{1}{3}\)

=>\(x=\dfrac{2}{3}-\dfrac{1}{3}=\dfrac{1}{3}\)

d: \(1-x=\dfrac{49}{65}\cdot\dfrac{5}{7}\)

=>\(1-x=\dfrac{49}{7}\cdot\dfrac{5}{65}=\dfrac{7}{13}\)

=>\(x=1-\dfrac{7}{13}=\dfrac{6}{13}\)

a )    x + 7/12 = 17/18 - 1/9 

        x + 7/12 = 17/18 - 2/18 

        x + 7/12 = 5/18 

              x     = 5/18 - 7/12

              x     = 10/36 - 21/36  

              x     =    -11/36 

b )   29/30 - ( 13/23 + x ) = 7/69 

       29/30 - 13/23 - x      = 7/69 

       29/30 - 39/69 - x      = 7/69

                  29/30 - x      = 7/69 + 39/69 

                  29/30 - x      = 46/69 

                             x      = 29/30 - 46/69 

                             x      =  3/10 

c ) x + 1/4 - 1/3 = 7/46

     x + 3/12 - 4/12 = 7/46

     x + -1/12          = 7/46

              x            = 7/46 + 1/12

              x            = 65/276 

 Tk mình nha !!! Chúc học giỏi !!! 
Ai thấy đúng TK mình nhé !!!! 

23/31 χ  5/46 - 3/62 = 5/62 - 3/62 = 1/31 ;                                         4/15 χ 7/16 χ 5/4 = 7/60 χ 5/4 = 7/48

A )  2/17 + 30/46 + 15/17 + 4/49 + 8/23=102/49

B ) 5/8 x ( 19/31 x 8/5 )=19/31

C ) 7/9 x 8/15 x 9/7 x 15/4=2

D ) 11/12 x 24/7 x 21/22=3

nhìu quá nên mk chỉ cho kết quả thôi nha ^-^!!!

a. 23 . ( 42 - x ) = 46

42 - x = 46 : 23

42 - x = 2

x = 42 - 2

x = 40

b. 7x - 8 = 41

7x = 41 + 8

7x = 49

x = 49 : 7

x = 7

c. 125 - 5(x + 3) = 15

5(x + 3) = 125 - 15

5(x + 3) =  110

x + 3 = 110 : 5

x + 3 = 22

x = 22 - 3

x = 19

a) 23 . ( 42 - x) = 46 => 42 - x = 46 : 23 = 2

=> x = 42 - 2 = 40

b) 7x - 8 = 41 => 7x = 41 + 8 = 49 => x = 49 : 7 = 7

c) 125 - 5.(x+3) = 15 => 5.(x+3) = 125 - 15 = 110 => x + 3 = 110 : 5 =22

=> x = 22 - 3 = 19

Thank you !

a) (-68) + (-72) + 2017 + (-28) + 168

= (-68 + 168) + [(-72) + (-28)] + 2017

= 100 + (-100) + 2017

= 0 + 2017

= 2017

Câu hỏi khác của Nguyễn Minh Anh

b) |-28| + (129 - 182 + 99) - (129 + 199 - 182)

= 28 + 129 - 182 + 99 - 129 - 199 + 182

= (129 - 129) - (182 - 182) + (99 - 199) + 28

= 0 - 0 + (-100) + 28

= -72