Viết số thích hợp vào ô trống: a) 48/84= 24/= /21= 4/ b) 42/72=/24= 7/ c) 25/75= 5/= 1/ d) 81/54= 27/= /6= 3/

`a ) 48/84 = (48 : 2)/(84 : 2) = 24/42 = (24 : 2)/(42 : 2) = 12/21 = (12 : 3)/(21 : 3) = 4/7`

Vậy `48/84 = 24/42 = 12/21 = 4/7`

`b ) 42/72 = (42 : 3)/(72 : 3) = 14/24 = (14 : 2)/(24 : 2) = 7/12`

Vậy `42/72 = 14/24 = 7/12`

`c ) 25/75 = (25 : 5)/(75 : 5) = 5/15 = (5 : 5)/(15 : 5) = 1/3`

Vậy `25/75 = 5/15 = 1/3`

`d ) 81/54 = (81 : 3)/(54 : 3) = 27/18 = (27 : 3)/(18 : 3) = 9/6 = (9 : 3)/(6 : 3) = 3/2`

Vậy `81/54 = 27/18 = 9/6 = 3/2`

`#dtkc`

$@Haru$

`a)`

`48/84=`$\dfrac{48 : 2}{84 : 2}$`=24/42`

`24/42=`$\dfrac{24 : 2}{42 : 2}$`= 12/21`

`12/21=`$\dfrac{12 : 3}{21 : 3}$`=4/7`

`=>` Hoàn thành: `48/84=24/42=12/21=4/7`

 `b)`

`42/72=`$\dfrac{42 : 3}{72 : 3}$`= 14/24`

`14/24=`$\dfrac{14 : 2}{24 : 2}$`=7/12`

`=>` Hoàn thành: `42/72=14/24=7/12`

`c)`

`25/75=`$\dfrac{25 : 5}{75 : 5}$`= 5/15`

`5/15=`$\dfrac{5 : 5}{15 : 5}$`= 1/3`

Hoàn thành: `25/75=5/15=1/3`

`d)`

`81/54=`$\dfrac{81 : 3}{54 : 3}$`=27/18`

`27/18=` $\dfrac{27 : 3}{18 : 3}$`=9/6`

`9/6 =`$\dfrac{9 : 3}{6 : 3}$`= 3/2`

`=>` Hoàn thành: `81/54= 27/18= 9/6= 3/2`