427 x 14 + 427 x 16 

= 427 x ( 14 + 16 ) 

= 427 x 30 

= 12810

a. 427 x 14 + 427 x 16

   = 427 x (14 + 16)

   = 427 x 30

   = 12810

HT và $$$

c ) 815 - 23 - 77 + 185 

= ( 815 + 185 ) - ( 23 + 77 )

= 1000 - 100 = 900

m ) 8 x 427 x 3 + 6 x 573 x 4

= 24 x 427 + 24 x 573

= 24 x ( 427 + 573 ) 

= 24 x 1000

= 24000

g ) 52 - 42 + 37 + 28 - 38 + 63

= ( 52 + 28 ) - ( 42 + 38 ) + ( 37 + 63 )

= 80 - 80 + 100

= 0 + 100

= 100

h ) 35 x 18 - 9 x 70 + 100

= 7 x 5 x 9 x 2 - 9 x 7 x 5 x 2 + 100

= 0 + 100

= 100

n ) 2008 x 867 + 2009 x 133

= 2008 x 867 + ( 2008 + 1 ) x 133

= 2008 x 867 + 2008 x 133 + 133

= 2008 x ( 867 + 133 ) + 133

= 2008 x 1000 + 133

= 2008000 + 133

= 2008133

i ) 326 x 78 + 327 x 22

= 326 x 78 + ( 326 + 1 ) x 22

= 326 x 78 + 326 x 22 + 22

= 326 x ( 78 + 22 )  + 22

= 326 x 100 + 22

= 32600 +22

= 32622

q ) ( 20 + 21 + 22 + 23 + 24 + 25 ) x ( 16 - 2 x 8 ) 

= ( 20 + 21 + 22 + 23 + 24 + 25 ) x ( 16 - 16) 

= ( 20 + 21 + 22 + 23 + 24 + 25 ) x 0

= 0

thank bạn

125 x 12 + 12 x 874 + 12

=       ( 125 + 874 + 1 ) x 12

=            1000  x  12

=             12 000

12 x 3 + 12 x 8 - 12

=12 x 3 + 12 x 8 - 12x1

=12x(3+8-1)

= 12 x 10

= 120

= 12 x ( 3 + 8 - 1)

= 12 x 10

= 120

12 x 3 + 12 x 8 - 12

= 12 x 3 + 12 x 8 - 12 x 1

= 12 x ( 3 + 8 - 1)

= 12 x 10

= 120

\(665:7\) x \(12\)

\(=95\) x \(12\)

\(=1140\)

$665:7$ x $12$

$=95$ x $12$

$=1140$

$\mathrm{Nha\; tick\; mình\; với}$

665 : 7 x 12 

=95 x 12 

= 1140

=125 x 12 +12 x 874 +12 x 1

=12x( 125 + 874 +1)

=12 x 1000

=12000

=12.(125+874+1)

=12.1000

=12000

125 x 12 + 12 x 874 + 12

= 12 x ( 125 + 874 + 1 )

= 12 x 1000

= 12000

142 x 12 + 42 x 18

= 142 x (12 +18)

= 142 x 30 = 4260

2350 x 0,48 + 0,4 x 765 x 12

= 2350 x 0,48 + ( 0,4 x 12 ) x 765

= 2350 x 0,48 + 4,8 x 765

= 235 x ( 10 x 0,48 ) + 4,8 x 765

= 235 x 4,8 + 4,8 x 765

= 4,8 x ( 235 + 765 )

= 4,8 x 1000

= 4800

_HT_

91,46 x (12-1-1)

=91,46 x 10

=914,6

Cảm ơn bạn