19/11 + [8/13 + 3/11]

=19/11+ 3/11+ 8/13

= 2 + 8/13

= 34/13

=\(\frac{19}{11}+\frac{3}{11}+\frac{8}{13}\)

=\(2+\frac{8}{13}\)

=\(2\frac{8}{13}\)

19/11+(8/13+3/11)=(19/11+3/11)+8/13=2+8/13=26/13+8/13=34/13

\(\frac{4}{15}+\frac{8}{13}+\frac{11}{15}+\frac{5}{13}\)

\(=\left(\frac{4}{15}+\frac{11}{15}\right)+\left(\frac{8}{13}+\frac{5}{13}\right)\)

\(=\frac{15}{15}+\frac{13}{13}\)

\(=1+1\)

\(=2\)

Chúc bạn học tốt nha !!! 

\(\frac{4}{15}+\frac{8}{13}+\frac{11}{15}+\frac{5}{13}\)

\(=\left(\frac{4}{15}+\frac{11}{15}\right)+\left(\frac{8}{13}+\frac{5}{13}\right)\)

\(=1+1\)

\(=2\)

=(4/15+11/5)+(8/13+5/13)

=37/15+1=52/15

k mink nha

a) 3/5x7/9+11/9x3/5

=3/5 x(7/9+11/9)

= 3/5x2

=6/5

b)14/13:1/2+3/13x2-2x7/13

= 14/13 x 2 +3/13 x2 - 2x7/13

=2 x (14/13 +3/13 -7/13)

= 2 x 10/13

= 20/13

a) 3/5 x 7/9 + 11/9 x 3/5 - 3/10

=  3/5 x 7/9 + 11/9 x 3/5 - 3/5 x 2

=  3/5 x ( 7/9 + 11/9 - 2 )

=  3/5 x 0

=  0

b) 14/13 : 1/2 + 3/13 x 2 - 2 x 7/13

=  14/13 x 2/1 + 3/13 x 2 - 2 x 7/13

=  ( 14/13 + 3/13 - 7/13 ) x 2

=  10/13 x 2 = 20/13

chẳng hiể gì cả

2x25x50xx8=(25x8)x(50x2)=200x100=20000

12x11+21x11+11x33=11x(12+21+33)=11x66=726

2*25*50*8

=(2*50)*(25*8)

=100*200=20000

12*11+21*11+11*33

=11*(12+21+33)

=11*66=676

2 x 25 x 50 x 8  = (8 x 25) x (50 x 2) = 200 x 100 = 20000

b) 12 x 11 + 21 x 11 + 11 x 13 = 11 x (12 + 21 + 33) 

= 11 x 66 = 726

20,11x96+20,11:0,25

=20,11x96+20,11x4

=20,11x100

=201,1

20, 11×96+20, 11:0, 25

= 20,11 x 96 + 20,11 x 4

= 20,11 x ( 96 + 4 )

= 20,11 x 100

= 2011

   20,11 x 96 + 20,11 : 0,25

= 20,11 x 96 + 20,11 x 4

= 20,11 x (96+4)

= 20,11 x 100

= 2011

bn ơi hình như sai đề rồi , số cuối cùng là 17/72

Giải thích hơi dài, tớ chỉ ghi đ/s thôi.

Đ/s: 1.

20/11*33/23*69/180=20*33*69/11*23*180=9/9=1

( 23 + 47) + (11 + 49) = 50 + 50 = 100

(4. 25) . (7 . 11) = 100 . 77 = 7700

23 + 47 + 11 + 49

=( 23 + 47 ) + (11+49)

= 70+60

=130

4.7.11.25

= (4.25) . (7.11)

=100 . 77

= 7700

k mình nha bn

\(23+47+11+49\)

\(=\left(23+47\right)+\left(11+49\right)\)

\(=70+60\)

\(=130\)

\(4.7.11.25\)

\(=\left(4.25\right).\left(7.11\right)\)

\(=100.77\)

\(=7700\)