18 x \(\dfrac{19191919}{21212121}\)+\(\dfrac{88888}{99999}\)

=18 x \(\dfrac{19}{21}\)+ \(\dfrac{8}{9}\)

=\(\dfrac{114}{7}\)+ \(\dfrac{8}{9}\)

= \(\dfrac{1082}{63}\)

= 18 x \(\left(\frac{19.1010101}{21.1010101}+\frac{8.11111}{9.11111}\right)\)= 18 x ( \(\frac{19}{21}+\frac{8}{9}\)) = 9 x 2 ( \(\frac{57+56}{63}\))

= 9 x 2 x \(\frac{113}{63}\)=\(\frac{226}{7}\)

dũng làm chẳng  hiểu gì cả

bài này bằng \(\frac{1082}{63}\)

= 18 ( 19/21 + 8/9)

= 18.113/63

=226/7 

\(=18x\frac{19x1010101}{21x1010101}+\frac{8x11111}{9x11111}=18x\frac{19}{21}+\frac{8}{9}\)

sao khong có kết quả hả bạn

\(18\cdot\left(\frac{19191919}{21212121}+\frac{88888}{99999}\right)\)

\(=18\cdot\left(\frac{19}{21}+\frac{8}{9}\right)\)

\(=18\cdot\frac{113}{63}\)

\(=\frac{678}{21}\approx32,286\)

nếu như bạn học lớp 6 rùi thì í thứ 3 là -21143 nha 

999 + 888 = 1887

99999 + 16661 - 88888 = 27772

246669 - 267812 = -21143

1887

27772

-21143

   9 x ( 262626/272727 + 88888/99999 )

= 9 x ( 26/27 + 8/9 )

= 9 x 50/27

= 50/3

k mình nha

18 x ( 19 x 1010101 / 21 x 1010101 + 8 x 11111/ 9x 11111)

= 18 x ( 19/21 + 8/9 )

= 18 x 19 / 21 + 18 x 8/9

= 6x3x19/7x3 + 9x2x8/9 = 6x19/7 + 16

= 226/7

=9*(26/27+8/9)

=9*50/27

=50/3