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

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

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

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

\(=1+1\)

\(=2\)

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

M = \(\frac{9}{40}\)- \(\frac{11}{60}\)+\(\frac{13}{84}\)- \(\frac{15}{112}\)

M = 378/1680 - 308/1680+ 260/1680- 225/1680

M = 105/1680

\(\frac{9}{40}-\frac{11}{60}+\frac{13}{84}-\frac{15}{112}=\frac{27}{120}-\frac{22}{120}+\frac{13}{84}-\frac{15}{112}=\frac{1}{24}+\frac{13}{84}-\frac{15}{112}=\frac{7}{168}+\frac{26}{168}-\frac{15}{112}=\frac{11}{56}-\frac{15}{112}=\frac{22}{112}-\frac{15}{112}=\frac{7}{112}=\frac{1}{16}\)

Cách thuân tiện nè:

M = ( 9/40 - 11/60) + 13/84-15/112

M=(  27/120-22/120) + 13/84 - 15/112

M = 1/24 + 13/84 - 15/112

M= ( 1/24 + 13/84) - 15/112

M = (7/168 + 26/168) - 15/112

M = 33/168 - 15/112 

M = 11/56 - 15/112

M = 22/112 - 15/112

M = 7/112

1/16 nha bn

1/16 nha bạn

\(\frac{1}{16}\)

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

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

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

=   22/11 + 8/13

= 2 + 8/13

= 34/13

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

k mk nha mk k lai

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

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