18 x 32,7 + 3 x 51,2 x 6 + 9 x 2 x 16,1

= 18 x 32,7 + (6 x 3) x 51,2 + (9 x 2) x 16,1

= 18 x 32,7 + 18 x 51,2 + 18 x 16,1

= 18 x (32,7 + 51,2 + 16,1)

= 18 x 100

= 1800

`18xx32,7+3xx51,2xx6+9xx2xx16,1`

`=18xx32,7+18xx51,2+18xx16,1`

`=18xx(32,7+51,2+16,1)`

`=18xx100`

`=1800`

18 x 32,7 + 3 x 51,2 x 6 + 9 x 2 x 16,1

= 18 x 32,7 + (6 x 3) x 51,2 + (9 x 2) x 16,1

= 18 x 32,7 + 18 x 51,2 + 18 x 16,1

= 18 x (32,7 + 51,2 + 16,1)

= 18 x 100

= 1800

`18xx32,7+3xx51,2xx6+9xx2xx16,1`

`=18xx32,7+18xx51,2+18xx16,1`

`=18xx(32,7+51,2+16,1)`

`=18xx100`

`=1800`

= 25 x 75/100 + 75 x 0.92 + 25 x 0.25 + 75 x 8/100
= 25 x 0.75 + 75 x 0.92 + 25 x 0.25 + 75 x 0.08
= 25 x ( 0.75 + 0.25 ) + 75 x ( 0.92 + 0.08 )
= 25 x 1 + 75 x 1 
= ( 25 + 75 ) x 1 
= 100 x 1
= 100

2345 x 25 + 2345 x 75 + 2345

= 2345 x (25+75+1)

= 2345 x 101

=236845

\(=2345\times\left(25+75+1\right)\)
\(=2345\times101\)
\(=236845\)

=236845

\(A=0,36.350+0,9.45.4+3.20.12\)
\(A=0,36.350+0,36.45+3,6.20\)
\(A=0,36.350+0,36.45+0,36.10.20\)
\(=0,36.\left(350+45+20.10\right)\)
\(A=0,36.595\)
\(A=214,2\)

\(b.12,8.3,2-y:4,6=35,06\)
\(40,96-y:4,6=35,06\)
\(y:4,6=40,96-35,06\)
\(y:4,6=5,9\)
\(y=5,9.4,6\)
\(y=27,14\)

\(y+y.\frac{3}{2}\)\(+y:\frac{2}{7}\)\(=21\)
\(y.1+y.\frac{3}{2}\)\(+y.\frac{7}{2}\)\(=21\)
\(y(1+\frac{3}{2}+\frac{7}{2}\)\()=21\)
\(y.6=21\)
\(y=\frac{21}{6}\)

\(1.a.4,47x6,1+2,53x6,1=\left(4,47+2,53\right)x6,1\)

\(=7x6,1\)

\(=42,7\)

\(b.4,56:0,57x6,3-4,8=8x6,3-4,8\)

\(=50,4-4,8\)

\(=45,6\)

\(c.\frac{13}{4}x\frac{5}{7}=\frac{65}{28}\)

\(d.\frac{7}{2}:\frac{21}{4}=\frac{28}{42}\)

\(2.a.15\%\)của\(450kg=67,5kg\)

\(b.25\%\)của\(800m=200m\)

\(c.75\%\)của\(90\)tấn\(67,5\)tấn

\(d.16\%\)của\(320m=51,2m\)

a) 4,47 x 6,1 + 2,53 x 6,1

= 6,1 x (4,47+2,53)

= 6,1 x  7

= 42,7

b) 4,56 : 0,57 x 6,3 - 4,8

=     8     x   6,3   -   4,8

=          50,4      -   4,8

= 45,6

c)\(1\frac{3}{4}\times\frac{5}{7}=\frac{7}{4}\times\frac{5}{7}=\frac{5}{4}\)

d) \(\frac{7}{2}:2\frac{1}{4}=\frac{7}{2}:\frac{9}{4}=\frac{7}{2}\times\frac{4}{9}=\frac{28}{18}=\frac{14}{9}\)

mỏi quá r bn làm tiếp nhé

1/

a) 4,47x6,1+2,53x6,1                               b)4,56:0,57x6,3-4,8

=6,1x(4,47+2,53)                                      =8x6,3-4,8

=6,1x7                                                    =50,4-4,8

=42,7                                                     =45,6

c)13/4x5/7                                              d)7/2:21/4

=65/28                                                    =7/2x4/21

                                                             =28/42

2/

a)15% của 450kg=67,5kg

b)25% của 800m=200m

c)75%của 90 tấn=67,5 tấn

d)16% cua 320m=51,2m

mình làm nhanh nhất nha :D

30x25x7x8

=(30x7)x(25x8)

=210x200

=42000

75x8x12x14

=(75x12)x(8x14)

=900x112

=100800

A) =(30*7)*(25*8)

=210*200

=4200 

B)=(75*8)*(12*14)

=600*168
=100800

a, 20,22 x 103 - 202,2 x 10 - 20,22 x 3

= 202,2 x 10,3 - 202,2 x 10 - 202,2 x 0,3

= 202,2 x( 10,3 - 10 - 0,3)

= 202,2 x ( 0,3 - 0,3)

= 202,2 x 0

=0 

b, 5,8 x 6,3 - 4,9 x 2,6 + 3,7 x 6,3 + 4,9 x 12,6

= ( 5,8 x 6,3 + 3,7 x 6,3) + ( 12,6 x 4,9 - 4,9 x 2,6 )

= 6,3 x ( 5,8 + 3,7) + 4,9 x ( 12,6 - 2,6)

= 6,3 x 9,5  + 4,9 x 10

= 59,85 + 49

= 108,85 

mong mọi người giúp mình tối nay mình cần gấp ạ