a; \(\dfrac{3}{11}\) + \(\dfrac{5}{-9}\) + \(\dfrac{4}{11}\) - \(\dfrac{4}{9}\) + \(\dfrac{3}{17}\) + \(\dfrac{15}{11}\)

= (\(\dfrac{3}{11}\) + \(\dfrac{4}{11}\) + \(\dfrac{15}{11}\)) - (\(\dfrac{5}{9}\) + \(\dfrac{4}{9}\)) + \(\dfrac{3}{17}\)

= 2 - 1 + \(\dfrac{3}{17}\)

= 1 + \(\dfrac{3}{17}\)

= \(\dfrac{20}{17}\) 

c; N = \(\dfrac{\dfrac{5}{7}-\dfrac{5}{9}-\dfrac{5}{11}}{\dfrac{15}{7}+\dfrac{15}{9}+\dfrac{15}{11}}\)

   Phải là - \(\dfrac{5}{7}\) chỗ tử số mới đúng em nhé!

d; \(\dfrac{4+\dfrac{4}{73}\times\dfrac{1}{23}}{5+\dfrac{5}{73}\times\dfrac{1}{23}}\)

= \(\dfrac{4\times\left(1+\dfrac{1}{73\times23}\right)}{5\times\left(1+\dfrac{1}{73\times23}\right)}\)

=  \(\dfrac{4}{5}\)

`#3107.101107`

\(\dfrac{5}{7}\times\dfrac{6}{11}+\dfrac{5}{11}\times\dfrac{1}{7}-\dfrac{5}{7}\times\dfrac{14}{11}\\ =\dfrac{5}{7}\times\dfrac{6}{11}+\dfrac{5}{7}\times\dfrac{1}{11}-\dfrac{5}{7}\times\dfrac{14}{11}\\ =\dfrac{5}{7}\times\left(\dfrac{6}{11}+\dfrac{1}{11}-\dfrac{14}{11}\right)\\ =\dfrac{5}{7}\times\left(-\dfrac{7}{11}\right)\\ =-\dfrac{5}{11}\)

nhanh k 10 k lun

nhyhvgfh

a, 6/7, 6/15, 6/17, 6/21

2.08813781251 nhé

bằng 3845/429

Đ/S là 3845/429

Đặt \(A=\frac{3}{5}+\frac{6}{11}+\frac{7}{11}+\frac{2}{5}+\frac{16}{11}+\frac{19}{13}\)

\(A=\left(\frac{3}{5}+\frac{2}{5}\right)+\left(\frac{6}{11}+\frac{7}{11}+\frac{16}{11}\right)+\frac{19}{13}\)

\(A=1+\frac{29}{11}+\frac{19}{13}\)

\(A=\frac{11}{11}+\frac{29}{11}+\frac{19}{13}=\frac{40}{11}+\frac{19}{13}=\frac{729}{143}\)

@Phạm Thị Mai Anh , @ngân sai kết quả với lại không có lời giải :v

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1.1+1.1+1.1+1.1+1.1/1.1+1.1+9.3+6.8+.2