a/   100 . 37 + 37. 37 + 200 . 63 - 63 . 63\

  =  37 .[ 100+ 37 ]   + 63 . [ 200 - 63 ]  

  =    37. 137             +  63 . 137 

  =    137. [ 37 + 63 ] 

  =   137 . 100 = 13700

b/  84 + 14 .6 + 7 . 12 + 21. 4 + 3.28 

=  84 + 84 +  84 + 84 +84

= 84. 5 = 420 

[ dấu " ." là " x" nha ] đừng quên tích cho tui 

a, 13700

Ta có:460+850x4=a+200/4

=>800=a+200/4

=>800x4=a+200

=>3200=a+200

=>a=3200-200=3000

ủng hộ nhak

460+85x4=(X+200):4

460+340=(X+200):4

     800   =(X+200):4

                X+200=800x4

                X+200=  3200

                X        =  3200-200

                X        =       3000.

K nhé Nguyễn Phương Chi.

X – 60 : 15 = 20,5

=> X – 60  = 307,5

=> X   = 367,5

 X : 4 + 12 = 23

=>  X : 4 = 11

=>  X  = 44

 ( x – 60 ) : 15 = 20

=> x – 60  =  300

=>  x  =  360

 3 .(x + 7)- 15= 27

=>  3 .(x + 7)  = 42

=>  x + 7  = 14

=>  x  =  7

 2. ( x – 5 )- 17 = 24 + 6 x 1,5

=>  2. ( x – 5 )  - 17  =  33

=>   2. ( x – 5 ) = 50

=>  x - 5  =  25

=>  x  =  30

\(a,x-60:15=20,5\)

\(x-4=20,5\)

\(x=20,5+4=24,5\)

\(b,x:4+12=23\)

\(x:4=23-12=11\)

\(x=11.4=44\)

\(c,\)\(\left(x-60\right)\)\(:15=20\)

\(x-60=20.15=300\)

\(x=300+60=360\)

\(d,3\left(x+7\right)\)\(-15=27\)

\(3\left(x+7\right)\)\(=27+15=42\)

\(x+7=42:3=14\)

\(x=14-7=7\)

\(e,2\left(x-5\right)\)\(-17=24+6.1,5=24+9=33\)

\(2\left(x-5\right)\)\(=33+17=50\)

\(x-5=50:2=25\)

\(x=25+5=30\)

=>........................

\(460+85x4=\left(y+200\right):4\)

\(460+340=\left(y+200\right):4\)

\(800=\left(y+200\right):4\)

\(y+200=800x4\)

\(y+200=3200\)

\(y=3200-200\)

\(y=3000\)

460 + 85 × 4 = y + 200/4

460 + 340 = y + 50

y + 50 = 800

y = 800 - 50

y = 750

3636 : ( 12x - 91 ) = 36

12x - 91 = 3636 :36

12x - 91 = 101

12x        = 101 + 91

12x       = 192

x          = 192 : 12

x          =  16 

vậy x = 16

460 + 85 . 4 = ( x + 200 ) : 4

460 + 340    = ( x  + 200 ) : 4

800             = ( x + 200 ) : 4

( x + 200 ) : 4 = 800

x + 200          = 800 . 4

x + 200          = 3200

x                   = 3200 - 200

x                   =  3000

vậy x = 3000

k mk nha bạn

thanks nhìu ^,^

\(3636:\left(12x-91\right)=36\)

\(\Rightarrow12x-91=3636:36\)

\(\Rightarrow12x-91=101\)

\(\Rightarrow12x=101+91\)

\(\Rightarrow12x=192\)

\(\Rightarrow x=16\)

\(460+85\cdot4=\left(x+200\right):4\)

\(\Rightarrow460+340=\left(x+200\right):4\)

\(\Rightarrow800=\left(x+200\right):4\)

\(\Rightarrow x+200=800\cdot4\)

\(\Rightarrow x+200=3200\)

\(\Rightarrow x=3200-200\)

\(\Rightarrow x=3000\)

óc đậu phộng

a, 2 x 15 + 2 x 84 + 2

= 2 x (15 + 84 + 1)

= 2 x 103

= 206

\(a,5\cdot\left(x+35\right)=515\)

              \(x+35=515:5\)

              \(x+35=103\)

                         \(x=103-35\)

                          \(x=68\)

a)x +35=103                         c)460 +340=(x+200):4

  x=68                                    800=(x+200):4

b)(x+ 40).15=900                    x+200=3200

  x+40=60                             x=300

  x=20

câu b cậu viết sai nha, đi