\(\dfrac{6}{25}+\dfrac{3}{5}=\dfrac{6}{25}+\dfrac{15}{25}=\dfrac{21}{25}\)

\(\dfrac{8}{3}-\dfrac{3}{9}=\dfrac{24}{9}-\dfrac{3}{9}=\dfrac{21}{9}=\dfrac{7}{3}\)

\(\dfrac{1}{2}:4=\dfrac{1}{2}\times\dfrac{1}{4}=\dfrac{1}{8}\)

\(\dfrac{3}{2}\times\left(\dfrac{4}{8}+\dfrac{5}{2}\right)=\dfrac{3}{2}\times3=\dfrac{9}{2}\)

\(\dfrac{6}{25}+\dfrac{3}{5}=\dfrac{21}{25}\)

\(\dfrac{8}{3}-\dfrac{3}{9}=\dfrac{7}{3}\)

\(\dfrac{1}{2}\div4=\dfrac{1}{8}\)

\(\dfrac{3}{2}\times\left\{\dfrac{4}{8}+\dfrac{5}{2}\right\}\)

\(=\dfrac{2}{3}\times3\)

\(=2\)

\(a,\dfrac{6}{11}+6+\dfrac{5}{7}=\dfrac{42+462+55}{77}=\dfrac{559}{77}\)

\(b,\dfrac{9}{8}\times\dfrac{3}{12}:\dfrac{5}{9}=\dfrac{9}{8}\times\dfrac{3}{12}\times\dfrac{9}{5}=\dfrac{243}{480}=\dfrac{81}{160}\)

\(c,\dfrac{8}{7}:4+2=\dfrac{8}{7}\times\dfrac{1}{4}+2=\dfrac{8}{28}+2=\dfrac{2}{7}+2=\dfrac{16}{7}\)

\(d,\dfrac{3}{5}+4:\dfrac{6}{4}=\dfrac{3}{5}+4\times\dfrac{4}{6}=\dfrac{3}{5}+\dfrac{8}{3}=\dfrac{49}{15}\)

ô hoooho bắt lỗi dc câu d nhee, sai đề ròi :)

\(2\frac{3}{4}\times3\frac{4}{5}\)

\(=\frac{11}{4}\times\frac{19}{5}\)

\(=\frac{209}{20}\)

thực hiện phép tính là cộng hay trừ hay nhân hay chia zậy bn

y=18/5

y=7/2

2/6 x y = 6/5 

y = 6/5 : 2/6

y = 18/5

7/10 : y = 1/5

Y = 7/10 : 1/5

y = 7/2

\(\dfrac{5}{12}+\dfrac{1}{6}=\dfrac{5}{12}+\dfrac{2}{12}=\dfrac{5+2}{12}=\dfrac{7}{12}\)

\(\dfrac{5}{12}+\dfrac{1}{6}=\dfrac{5}{12}+\dfrac{2}{12}=\dfrac{7}{12}\)

\(1-\dfrac{23}{47}=\dfrac{47}{47}-\dfrac{23}{47}=\dfrac{24}{47}\)

\(\dfrac{4}{5}x\dfrac{7}{8}=\dfrac{4x7}{5x8}=\dfrac{28}{40}=\dfrac{7}{10}\)

\(\dfrac{8}{5}:\dfrac{1}{4}=\dfrac{8}{5}x\dfrac{4}{1}=\dfrac{32}{5}\)

7/5+4/5   7/20-1/4         5/4x3/9      7/2 : 8

=7+4/5    =7/20-5/20      =5/4x1/3    =7/2x 1/8

=11/5       =7-5/20          =5/12         =7/16

                 = 1/10 

Nhớ tick đấy

đâu có biết tick...

a. x + \(\dfrac{3}{7}\)= \(\dfrac{2}{5}:\dfrac{18}{25}=>x+\dfrac{3}{7}=\dfrac{2}{5}\)x\(\dfrac{35}{18}=>x+\dfrac{3}{7}=\dfrac{7}{9}\)

=> x = \(\dfrac{7}{9}-\dfrac{3}{7}=\dfrac{49}{63}-\dfrac{27}{63}=\dfrac{22}{63}\)

b. \(x\) x \(\dfrac{5}{9}\)= \(\dfrac{4}{5}-\dfrac{1}{3}\)

=> \(x\) x \(\dfrac{5}{9}\)= \(\dfrac{12}{15}-\dfrac{5}{15}=>x\) x \(\dfrac{5}{9}\)= \(\dfrac{7}{15}\)

=> x = \(\dfrac{7}{15}:\dfrac{5}{9}\)

=> x = \(\dfrac{21}{25}\)

a,x + 3/7 = 2/5 : 18/35

   x + 3/7 = 7/9

   x          = 7/9 - 3/7

   x          = 22/63

vậy x = ...

b, X x 5/9 = 4/5 - 1/3

    X x 5/9 = 7/15

            X  = 7/15 : 5/9

            X  = 21/25

vậy X = ...

\(a.x+\dfrac{3}{7}=\dfrac{2}{5}:\dfrac{18}{35}\\x+\dfrac{3}{7}=\dfrac{2}{5}\times\dfrac{35}{18} \\ x+\dfrac{3}{7}=\dfrac{7}{9}\\ x=\dfrac{7}{9}-\dfrac{3}{7}\\ x=\dfrac{22}{63}\)

\(b.x\times\dfrac{5}{9}=\dfrac{4}{5}-\dfrac{1}{3}\\x\times\dfrac{5}{9}=\dfrac{7}{15}\\ x=\dfrac{7}{15}:\dfrac{5}{9}\\ x= \dfrac{21}{25}\)