Rút gọn:

\(\dfrac{2}{36}=\dfrac{2:2}{36:2}=\dfrac{1}{18}\)

\(\dfrac{8}{12}=\dfrac{8:4}{12:4}=\dfrac{2}{3}\)

Quy đồng mẫu số:

\(\dfrac{1}{18}=\dfrac{1}{18};\dfrac{2}{3}=\dfrac{2\cdot6}{3\cdot6}=\dfrac{12}{18}\)

Rút gọn:

\(\dfrac{2}{36}\) =\(\dfrac{2:2}{36:2}\)=\(\dfrac{1}{18}\)

\(\dfrac{8}{12}\)=\(\dfrac{8:4}{12:4}\)=\(\dfrac{2}{3}\)

Quy đồng mẫu :

Mẫu chung là 36

\(\dfrac{2}{36}\)=\(\dfrac{2\times1}{36\times1}\)=\(\dfrac{2}{36}\) và \(\dfrac{8}{12}\)=\(\dfrac{8\times3}{12\times3}\)=\(\dfrac{21}{36}\)

\(1235\cdot6789\cdot\left(630-315\cdot2\right):1996\)

\(=1235\cdot6789\left(630-630\right):1996\)

=0

160

640 : 4 = 160

What?

Cái gì vậy!!!

Sao dài thế?

điên hả bé?

78 x 15 + 78 x 85

= 78 x ( 85 + 15)

= 78 x 100

= 7800

  \(\dfrac{33}{69}\) = \(\dfrac{11}{23}\) = \(\dfrac{154}{322}\)

 \(\dfrac{9}{14}\) =  \(\dfrac{9\times23}{14\times23}\) = \(\dfrac{207}{322}\) 

Vậy các phân số \(\dfrac{9}{14}\) và \(\dfrac{33}{69}\) đã được quy đồng mẫu số các phân số thành các phân số: 

\(\dfrac{207}{322}\); \(\dfrac{154}{322}\); 

\(\dfrac{9}{14}=\dfrac{9\cdot69}{14\cdot69}=\dfrac{621}{966}\)

\(\dfrac{33}{69}=\dfrac{33\cdot14}{69\cdot14}=\dfrac{462}{966}\)

47000:25=1880

47000:25=1880

467 x 23 + 467 x 76 + 467
= 467 x 23 + 467 x 76 + 467 x 1
= 467 x (23 + 76 + 1)
= 467 x 100
= 46700

Lời giải:
$467\times 23+467\times 76+467$

$=467\times 23+467\times 76+467\times 1$

$=467\times (23+76+1)=467\times 100=46700$