650 x 34 + 34 x 2 x 135 + 34 x 80 

= 650 x 34 + 34 x 270 + 34 x 80

= 34 x ( 650 + 270 + 80 )

= 34 x 1000

= 34000

Tick nha 

650 x 34 + 34 x 2 x 135 + 34 x 80 

= 650 x 34 + 34 x 270 + 34 x 80

= 34 x ( 650 + 270 + 80 )

= 34 x 1000

= 34000

650 x 34 + 34 x 2 x 135 + 34 x 80 

= 650 x 34 + 34 x 270 + 34 x 80

= 34 x ( 650 + 270 + 80 )

= 34 x 1000

= 34000

Ta có:

=\(\dfrac{6x45x11x17}{15x12x34x33}\)

= \(\dfrac{6x15x3x11x17}{15x6x2x17x2x11x3}\)

= \(\dfrac{1}{2x2}\)

=\(\dfrac{1}{4}\)

Những chữ x ở trên là dấu nhân nhé

135 x 37 + 135 +  62 x 135

= 135 x 37 + 135 x 1 +  62 x 135

= 135 x ( 37 + 1 + 62)

 = 135 x 100

= 13500

`3/7+2/5+4/7`

`=(3/7+4/7)+2/5`

`=1+2/5`

`=5/5+2/5`

`=7/5`

`20/34+4/9+7/17`

`=(20/34+7/17)+4/9`

`=(20/34+14/34)+4/9`

`=34/34+4/9`

`=1+4/9`

`=9/9+4/9`

`=13/9`

`48xx2+96+48xx6`

`=48xx2+48xx2+48xx6`

`=48xx(2+2+6)`

`=48xx10`

`=480`

câu thứ hai thì làm như này em nhé:

    \(\dfrac{20}{34}\) + \(\dfrac{4}{9}\) + \(\dfrac{7}{17}\)

= (\(\dfrac{20}{34}\) + \(\dfrac{7}{17}\)) + \(\dfrac{4}{9}\)

=  (\(\dfrac{10}{17}\) + \(\dfrac{7}{17}\)) + \(\dfrac{4}{9}\)

= 1 + \(\dfrac{4}{9}\)

= \(\dfrac{13}{9}\)

$#Shả$

`A)=5/17xx(15/34+19/34)`

`=5/17xx1=5/17`

`B)=(13/12+7/12)+1/3`

`=5/3+1/3=2`

21/11 x 22/17 x 68/63 = 952/357

5/14 x 7/13 x 6/25=3/65

\(\frac{21}{11}X\frac{22}{17}X\frac{68}{63}=\frac{952}{357} \)

\(\frac{5}{14}X\frac{7}{13}X\frac{6}{25}=\frac{3}{65}\)

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