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

a) 20x4+20x3+20x3

= 20 x ( 4+3 + 3)

= 20 x10

= 200

 b) (6x9-54)x(25 +26+27+.........41+42)

= 0 x (25 +26+27+.........41+42)

= 0 

20x4+20x3+20x3

= 20 x ( 4+3 + 3)

= 20 x10

= 200

 b) (6x9-54)x(25 +26+27+.........41+42)

= 0 x (25 +26+27+.........41+42)

= 0 

a) = 20 x ( 4 + 3 + 3 )

   = 20 x 10

  = 200

b) = 0 x ( 25+26+27+....41+42)

= x

 = 2600

chi tiết giúp mk nha

\(26.17+38.26+26.44+26=26\left(17+38+44+1\right)=26.100=2600\)

=\(689^2.101=47946821\)

A, 27 X 45 + 45 X 74 - 45 =

     27 X 45 + 74 X 45 - 45 X 1=

     45X[ 27+74 - 1] = 

     45 X 100          = 

4500

B,[ 54 X 28+12 X 54 ] : 36 =

   [ 54 X 28 + 54 X 12] : 36=

   [ 54 X [ 28 + 12       ] :36=

  [54 X 40 ]     : 36=

2160   : 36=

60

MÌNH CÓ SAI CHỖ NÀO BẠN CỐ GẮNG TÌM CÁCH KHÁC NHÉ !

101.9,42-9,42+25.2,32

=9,42.(101-1)+58

=9,42.100+58

=942+58=1000

   101 x 9,42 - 9,42 + 25 x 2,32

=  101 x 9,42 - 9,42 x 1 + 25 x 2,32

= 9,42 x ( 101 - 1) + 58

= 9,42 x 100 + 58

= 942 + 58

= 1000

123 x 54 + 123 x 46

= 123 x (54 +46) = 123 x 100

= 12300

=(101 - 1) x 0,75

=100 x 0,75

=75

\(7,89\times54-7,89\times54-7,89\)

\(=7,89\times\left(54-54\right)-7,89\)

\(=7,89\times0-7,89\)

\(=0-7,89\)

\(=-7,89\)

 = 0 - 7,89 = -7,89

k mk nha

7,89.54-7,89.54-7,89

=(7,89.54-7,89.54)-7,89

=0-7,89=-7,89