566 x 23 + 466 x 23 + 23 

   = ( 566 + 466 + 1 ) x 23

   =            1033 x 23

   =        ( 1000 x 23) + (30 x 23) + (3 x 23)

   =              23000 +  690 + 69 =     23759

         lưu ý: 23:23=1    

 566x23+433x23+23

=566x23+433x23+1x23

=(566 +433 + 23)x23

=1000 x 23

=23000

Lộn (566+433+1) nha

 27 x 782 + 72 x 782 + 782

=27 x 782 + 72 x 782 + 782 x 1

=782 x (27 +72 + 1)

=782 x 100

= 78 200

 642 - 29 + 329 - 42 + 100

= ( 642 - 42 ) + ( 329 - 29 ) + 100

=    600        +     300        + 100

=                   1000

Nhớ tk mình nha!

642 – 29 + 329 – 42 +100

= (642 – 42) + (329 – 29) + 100

=  600 + 300 + 100

= 1000 

 642-29+329-42+100

= ( 642 - 42 ) + ( 629 - 29 ) + 10

= 600 + 600 + 100

= 1200 + 100

= 1300

giúp mình với

\(a,\dfrac{7}{9}-\dfrac{2}{7}+\dfrac{2}{3}+\dfrac{4}{7}\\ =\left(\dfrac{7}{9}+\dfrac{6}{9}\right)+\left(\dfrac{4}{7}-\dfrac{2}{7}\right)\\ =\dfrac{13}{9}+\dfrac{2}{7}\\ =\dfrac{109}{63}\\ b,13,8+7-5,25+4,25\\ =\left(13,8+7\right)-\left(5,25-4,25\right)\\ =20,8-1\\ =19,8\)

a \(\left(\dfrac{4}{7}-\dfrac{2}{7}\right)+\left(\dfrac{7}{9}+\dfrac{2}{3}\right)=\dfrac{2}{7}+\left(\dfrac{7}{9}+\dfrac{6}{9}\right)=\dfrac{2}{7}+\dfrac{15}{9}=\dfrac{2}{7}+\dfrac{5}{3}=\dfrac{6}{21}+\dfrac{35}{21}=\dfrac{41}{21}\)

b \(20.8-1=19.8\)

a) 19,17x25x4=19,17(25x4)=19,17x100=1917

b)1,79x(8x125)=1,79x1000=1790

chúc bạn học tốt

A) =5

B) = 13440 pn nha

=5/4:(5/6+5/9+1/1)

=5/4:43/18

=45/86