\(\frac{4}{5}\)+ \(\frac{1}{5}\): \(\frac{-2}{15}\)= \(\frac{4}{5}\)+ \(\frac{1}{5}\)* \(\frac{-15}{2}\)=\(\frac{4}{5}\) + \(\frac{-3}{2}\)= \(\frac{-7}{10}\)

b = \(\frac{-7}{12}\). (\(\frac{3}{11}\)+ \(\frac{-14}{11}\)) + \(\frac{5}{6}\)= \(\frac{-7}{12}\). (-1) + \(\frac{5}{6}\)= \(\frac{7}{12}\)+ \(\frac{10}{12}\)= \(\frac{17}{12}\)

x-\(\frac{3}{5}\)x = \(\frac{2}{5}\)

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

=> x. \(\frac{2}{5}\)= \(\frac{2}{5}\)

=> x=1

Vậy x=1

a) \(\dfrac{4}{11}+\dfrac{5}{22}=\dfrac{8}{22}+\dfrac{5}{22}=\dfrac{13}{22}\)

b) \(3-\dfrac{3}{8}=\dfrac{3}{1}-\dfrac{3}{8}=\dfrac{24}{8}-\dfrac{3}{8}=\dfrac{21}{8}\)

c) \(\dfrac{9}{25}\times5=\dfrac{45}{25}=\dfrac{9}{5}\)

d) \(\dfrac{3}{7}\div4=\dfrac{3}{28}\)

a)

= 8/22 + 5/22

= 11/22

= 1/2

b)

= 24/8 - 3/8

= 21/8

c)

= 45/25

= 9/5

d)

= 3/7 x 1/4

= 3/28

:)

Bài 1 phần D

Bài 2:

\(\frac{1}{4}\)x\(\frac{5}{3}\):\(\frac{2}{7}\)

= \(\frac{5}{12}\): \(\frac{2}{7}\)

=\(\frac{35}{24}\)

k mình nhá, thanks !!!

AI KẾT BN KO!

TIỆN THỂ TK MÌNH LUÔN NHA!

KONOSUBA!!!

#)Trả lời :

a)   \(\frac{-1}{2}+\frac{2}{7}-\frac{5}{28}\)

    \(=\frac{-3}{14}-\frac{5}{28}\)

    \(=\frac{-11}{28}\)

b)  \(5\frac{3}{4}+\left(\frac{1}{9}-1\frac{3}{4}\right)\)

   \(=\left(5\frac{3}{4}-1\frac{3}{4}\right)+\frac{1}{9}\)

   \(=4+\frac{1}{9}\)

   \(=4\frac{1}{9}=\frac{37}{9}\)

c)  \(\frac{-5}{7}x\frac{2}{11}+\frac{-5}{7}x\frac{9}{11}+3\frac{5}{7}\)

   \(=\frac{-5}{7}x\left(\frac{2}{11}+\frac{9}{11}\right)+3\frac{5}{7}\)

   \(=\frac{-5}{7}x1+3\frac{5}{7}\)

   \(=\frac{-5}{7}+3\frac{5}{7}\)

   \(=\frac{-5}{7}+\frac{26}{7}\)

   \(=\frac{21}{7}=3\)

            #~Will~be~Pens~#

a) \(\frac{4}{7}:\frac{8}{11}=\frac{4}{7}\times\frac{11}{8}\)

                  \(=\frac{44}{56}=\frac{22}{23}\)

b) \(\frac{3}{5}+\frac{4}{5}:\frac{2}{5}=\frac{3}{5}+\frac{4}{5}\times\frac{5}{2}\)

                           \(=\frac{3}{5}+2\)

                             \(=\frac{13}{5}\)

a: 4/7:8/11=4/7x11/8=44/56=11/14

b: 3/5+4/5:2/5

= 3/5+4/5x5/2

= 3/5+10/5

=13/5

a, 13/6+5/8 : -3/4 - 7/12.4

= 13/6 + -5/6-7/3

=8/6-7/3

= -6/6

= -1

b, ( 73/5 - 21/3) + ( 4/3-43/5 )

= 73/5-21/3+4/3-43/5

=( 73/5-43/5)-(21/3-4/3)

= 6-17/3

=1/3

c, 7/5.4/9 +7/5: 9/16- 14/10.2/9

= 7/5.4/9 +7/5.16/9 - 14/45

=7/5.(4/9+16/9)-14/45

=7/5.20/9-14/45

= 140/45 - 14/45

= 126/45

Xong rùi nè! Nhưng bạn kiểm tra lại giùm nhé vì làm vào ban đêm nên hơi bất tiện

Trời ạ. 7 3/5 chứ k phải 73/5 -_-

ghi rõ thêm từ và nhé!

Bài 2 :

a) Tìm x 

\(x:\frac{2}{3}=\frac{1}{2}\) 

      \(x=\frac{1}{2}\times\frac{2}{3}\)

      \(x=\frac{1}{3}\)

Vậy \(x=\frac{1}{3}\)

b) Tính giá trị của biểu thức :

\(\frac{5}{7}\times\frac{3}{5}-\frac{10}{14}\times\frac{2}{15}\)

\(=\frac{5}{7}\times\frac{3}{5}-\frac{5}{7}\times\frac{2}{15}\)

\(=\frac{5}{7}\times\left(\frac{3}{5}-\frac{2}{15}\right)\)

\(=\frac{5}{7}\times\frac{7}{15}\)

\(=\frac{1}{3}\)

ủng hộ tớ nha. 

Bài 2:

a) x : 2/3 = 1/2

   x          = 1/2 x 2/3

  x           = 1/3

b) 5/7 x 3/5 - 10/14 x 2/15

= 3/7 - 5/7 x 2/15

= 3/7 - 2/21 (tự quy đồng)

= 1/3

làm lại.quy đồng cho mình cơ vũ như mai

\(\frac{6}{11}\cdot\frac{3}{14}+\frac{-5}{16}+\frac{3}{14}\cdot\frac{5}{11}+\frac{-3}{16}\)

\(=\frac{6}{11}\cdot\frac{3}{14}+\frac{3}{14}\cdot\frac{5}{11}+\frac{-5}{16}+\frac{-3}{16}\)

\(=\frac{3}{14}\cdot\left(\frac{6}{11}+\frac{5}{11}\right)+\left(\frac{-5}{16}+\frac{-3}{16}\right)\)

\(=\frac{3}{14}\cdot\frac{6+5}{11}+\frac{-5+\left(-3\right)}{16}\)

\(=\frac{3}{14}\cdot\frac{11}{11}+\frac{-8}{16}\)

\(=\frac{3}{14}\cdot1+\frac{-1}{2}\)

\(=\frac{3}{14}+\frac{-1}{2}\)

\(=\frac{3}{14}+\frac{-7}{14}\)

\(=\frac{3+\left(-7\right)}{14}\)\(=\frac{-4}{14}=\frac{-2}{7}\)

\(\frac{-5}{6}+\left(7x-\frac{1}{2}\right)\cdot\frac{2}{9}=-1\frac{1}{3}\)

       \(\frac{-5}{6}+\frac{14}{9}\cdot x-\frac{1}{9}=-\frac{4}{3}\)

                       \(\frac{14}{9}\cdot x-\frac{1}{9}=-\frac{4}{3}+\frac{5}{6}\)

                       \(\frac{14}{9}\cdot x-\frac{1}{9}=-\frac{1}{2}\)

                                   \(\frac{14}{9}\cdot x=-\frac{1}{2}+\frac{1}{9}\)

                                   \(\frac{14}{9}\cdot x=-\frac{7}{18}\)

                                              \(x=-\frac{7}{18}:\frac{14}{9}\)

                                              \(x=-\frac{1}{4}\)

a) \(5+\frac{1}{4}=\frac{20}{4}+\frac{1}{4}=\frac{21}{4}\)

b) \(7-\frac{3}{5}=\frac{35}{5}-\frac{3}{5}=\frac{32}{5}\)

b) \(2\times\frac{9}{11}=\frac{18}{11}\)

d) \(\frac{2}{34}:5=\frac{2}{34}:\frac{5}{1}=\frac{2}{34}\times\frac{1}{5}=\frac{2}{170}=\frac{1}{85}\)

ủng hộ nha.