=5/11x(27/21-2/7)

=5/11x(9/7-2/7)

=5/11x1

=5/11

\(\frac{5}{11}\cdot\frac{27}{21}-\frac{5}{11}\cdot\frac{2}{7}=\frac{5}{11}\cdot\left(\frac{27}{21}-\frac{2}{7}\right)=\frac{5}{11}\cdot1=\frac{5}{11}\)

5/11 nha

39x11+25x11 =(39+25)x11                                   

=64x11

=704

   67x11+58x11=(67+58)x11

  =125x11

=1375

39x11- 27x11

=(39-27)x11

=12x11

=132

Câu tự lấy ví dụ nhé

1) 39 x 11 + 25 x 11

  = 11 x ( 39 + 25 ) = 11 x 64 = 704

    67 x 11 + 58 x 11

  = 11 x ( 67 + 58 ) = 11 x 125 = 1375

   39 x 11 - 27 x 11

  = ( 39 - 27 ) x 11 = 12 x 11 = 132

1,

a,=4/7:4/9.3

=9/7.3

=27/7

b,=(7/11+4/11).5/6

=1.5/6

=5/6

`(6/7-2/7):4/9xx3=4/7xx9/4xx3=[4xx9xx3]/[7xx4]=27/7`

`7/11xx5/6+4/11xx5/6=(7/11+4/11)xx5/6=11/11xx5/6=5/6`

\(\dfrac{5}{13}\times\dfrac{7}{11}+\dfrac{5}{13}\times\dfrac{2}{11}+\dfrac{8}{13}\times\dfrac{9}{11}\)

\(=\dfrac{5}{13}\times\left(\dfrac{7}{11}+\dfrac{2}{11}\right)+\dfrac{8}{13}\times\dfrac{9}{11}\)

\(=\dfrac{5}{13}\times\dfrac{9}{11}+\dfrac{8}{13}\times\dfrac{9}{11}\)

\(=\dfrac{9}{11}\times\left(\dfrac{5}{13}+\dfrac{8}{13}\right)\)

\(=\dfrac{9}{11}\times1\)

\(=\dfrac{9}{11}\)

a) \(20,23\times21+20,23\times80-20,23\)

\(=20,23\times\left(21+80-1\right)\)

\(=20,23\times100\)

\(=2023\)

\(\dfrac{5}{13}\) \(\times\) \(\dfrac{7}{11}\) + \(\dfrac{5}{13}\) \(\times\) \(\dfrac{2}{11}\) + \(\dfrac{8}{13}\) \(\times\) \(\dfrac{9}{11}\)

= \(\left(\dfrac{5}{13}\times\dfrac{7}{11}+\dfrac{5}{13}\times\dfrac{2}{11}\right)\)+ \(\dfrac{8}{13}\) \(\times\) \(\dfrac{9}{11}\)

= \(\dfrac{5}{13}\)\(\times\) (\(\dfrac{7}{11}\) + \(\dfrac{2}{11}\)) + \(\dfrac{8}{13}\) \(\times\) \(\dfrac{9}{11}\)

= \(\dfrac{5}{13}\) \(\times\) \(\dfrac{9}{11}\) + \(\dfrac{8}{13}\) \(\times\) \(\dfrac{9}{11}\)

= \(\dfrac{9}{11}\) \(\times\)( \(\dfrac{5}{13}\) +\(\dfrac{8}{13}\))

= \(\dfrac{9}{11}\) \(\times\) 1

= \(\dfrac{9}{11}\)

(4/11+7/11)*5/6

=1*5/6=5/6

5/6.(4/11+7/11)

=5/6.1

=5/6

5/6 x (4/11 + 7/11) = 5/6 x 1 = 5/6

\(=\dfrac{11}{12}\left(\dfrac{2}{7}+\dfrac{4}{7}+\dfrac{1}{7}\right)=\dfrac{11}{12}\cdot1=\dfrac{11}{12}\)

=11/12

11/12 nha

2: \(=\dfrac{-2}{75}+\dfrac{5}{39}=\dfrac{33}{325}\)

3: \(=\dfrac{6}{11}\left(\dfrac{4}{9}+\dfrac{5}{9}\right)=\dfrac{6}{11}\)

4: \(=\dfrac{7}{19}\left(\dfrac{5}{13}+\dfrac{8}{13}-1\right)=-2\cdot\dfrac{7}{19}=-\dfrac{14}{19}\)

5: \(=\dfrac{2}{7}\left(\dfrac{4}{23}-\dfrac{27}{23}+1\right)=0\)

6: \(=\dfrac{3}{8}\left(\dfrac{3}{7}+\dfrac{4}{7}\right)+\dfrac{11}{8}=\dfrac{3}{8}+\dfrac{11}{8}=\dfrac{14}{8}=\dfrac{7}{4}\)

a: \(=\left(15-6-\dfrac{13}{18}\right):\dfrac{298}{27}-\dfrac{17}{8}:\dfrac{51}{40}\)

\(=\dfrac{149}{18}\cdot\dfrac{27}{298}-\dfrac{5}{3}=\dfrac{3}{2}-\dfrac{5}{3}=\dfrac{9-10}{6}=\dfrac{-1}{6}\)

b: \(=\dfrac{-16}{5}\cdot\dfrac{-15}{64}+\dfrac{-22}{15}:\dfrac{11}{2}\)

\(=\dfrac{3}{4}-\dfrac{4}{15}=\dfrac{29}{60}\)

c: \(=\dfrac{-7}{9}\left(\dfrac{4}{11}+\dfrac{7}{11}\right)+5+\dfrac{7}{9}=\dfrac{-7}{9}+\dfrac{7}{9}+5=5\)

d: \(=\dfrac{1}{2}\cdot\dfrac{4}{3}\cdot10\cdot\dfrac{1}{5}\cdot\dfrac{3}{4}=1\)

e: \(=\dfrac{4}{25}+\dfrac{11}{2}\cdot\dfrac{5}{2}+\dfrac{-23}{4}=\dfrac{204}{25}\)

5/11.5/7+2/7.5/11

=5/11.(5/7+2/7)

=5/11

15 x 7/15 x 4/9

=7 x 4/9

=28/9

5/11

28/9