a. 4125:15-405:15

   =(4125-405):15

   =3720:15

   =248.

b. 25x5x4x3

   = 25x4x5x3

   = 100x15

   =1500.

c. 236x20-36x20

   =(236-36)x20

   = 200x20

   =4000.

d) 785x214+215x214

= (785+215)x214

=  1000x214

=214000

A)  4125 : 15 - 405 : 15

=  ( 4125 - 405 ) : 15 = 3720 : 15 = 248

B)  25 x 5 x 4 x 3

=  ( 25 x 4 ) x ( 5 x 3 ) = 100 x 15 = 1500

C)  236 x 20 - 36 x 20

= ( 236 - 36 ) x 20 = 200 x 20 = 4000

D)  785 x 214 + 215 x 214

=  ( 785 + 215 ) x 214 = 1000 x 214 = 214 000

            Chúc bạn học tốt

có ai tính nhanh đượcc ko

a ) 4125 : 15 - 405 : 15
=    ( 4125 - 405 ) : 15 
=       3720          : 15
= 248
135 x 345 + 675 : 135
=   46575  +   5
=     46580
62385+237 x 165
=  62385 + 39105
=  101490
b )25 x 5 x 4 x 3
=  ( 25 x 3 ) x ( 5x 4 )
=     75        x   20 
=            1500
15400 : 25 : 4 
=  15400 : ( 25 x 4 )
=  15400 :      100
=      154
132039 - 1234 x 107 
= 132039 - 132038
=        1
c ) 236 x 20 - 36 x 20
=  ( 236 - 36 ) x 20 
=     200 x   20
=        4000
1224 : 24 + 1416 : 24
=  ( 1224 + 1416 ) : 24
=     2640   : 24
=      110

k giùm mk nha bn

http://123link.vip/lTSyH72

a ) 4125 : 15 - 405 : 15
=    ( 4125 - 405 ) : 15 
=       3720          : 15
= 248
b )25 x 5 x 4 x 3
=  ( 25 x 3 ) x ( 5x 4 )
=     75        x   20 
=            1500
c ) 236 x 20 - 36 x 20
=  ( 236 - 36 ) x 20 
=     200 x   20
=        4000
 

\(a.4125:15-405:15=\left(4125-405\right):15\)

                                             \(=3720:15=248\)

\(b.25\times5\times4\times3=\left(25\times4\right)\times\left(5\times3\right)\)

                                      \(=100\times15=1500\)

\(c.236\times20-36\times20=\left(236-36\right)\times20\)

                                                  \(=200\times20=4000\)

a.     4125 : 15  -  405 : 15 

    = ( 4125 - 405 ) : 15

    =  3720 : 15

    = 248

  b. 25 x 5 x 4 x 3 

  = ( 25 x 4 ) x ( 5 x 3 )

  = 100 x 15

  = 1500

c.  236 x  20 – 36 x 20

 = ( 236 - 36 ) x 20

 = 200 x 20

 = 4000

3 \(\times\) \(\dfrac{4}{15}\) + 2 \(\times\) \(\dfrac{4}{15}\) - 5 \(\times\) \(\dfrac{4}{15}\)

= \(\dfrac{4}{15}\) \(\times\) ( 3 + 2 - 5)

= \(\dfrac{4}{15}\) \(\times\) 0

= 0

0 nha

[3+2-5]nhan 4/15

=0        nhan4/15

=0

99 x 15 + 15 = 15 x ( 99 + 1) = 15 x 100 = 1500

= 15x 4 + 15 x 96

= 15x (4+96)

= 15x 100

=1500

15: 0,25+ 15 x 96 

15 x 4 + 15 x 96

15 x (4 + 96)

15 x 100

1500

= 11/11+ 15/15

= 1+ 1

= 2

= 11/11+ 15/15

= 1+ 1

= 2

tick cho mk

=(9/11+2/11)+(6/15+9/15)

=1+1

=2

= (5/6 + 7/6) + (4/15 + 11/15)
= 2 + 1

= 3 

=(5/6+7/6)+(4/15+11/15)

=12/6+15/15

=2+1

=3

đúng ko day

\(=\left(\dfrac{5}{6}+\dfrac{7}{6}\right)+\left(\dfrac{4}{15}+\dfrac{11}{15}\right)=\dfrac{12}{6}+1=2+1=3\)

=(5/6+7/6)+(4/15+11/15)

=12/6+15/15

=2+1

=3

= (5/6 + 7/6) + (11/15 + 4/15)

= 12/6 + 15/15

= 2 + 1

= 3