a) (42 x 43 + 43 x 57 + 43) - 360 : 4

  = 43 x ( 42 x 57) + 43 - 360 :4

  = 43 x 99 + 43 - 90

  = 4257 + 43 - 90

  = 4300 - 90

  = 4210

b) (372 - 194 x 4) + (981 : 9 - 13)

  = (372 - 776) + (109 - 13)

  = -404 + 96 

  = -308

c) 456 : 2 x 18 + 456 : 3 - 102

  = 228 x 18 + 152 - 102

  = 4104 + 152 - 102

  = 4256 - 102

  = 4154

  = 

a) (42.43+43.57+43)-360:4

=4300 - (360:4)

=4300- 90

=4210

b) (372 -194 .4 ) + ( 981 : 9 - 13 )

=712 + 69

=808

c) 456 : 2 . 18 + 456 : 3 - 102

= (456 : 2 . 18) + (456 : 3 - 102)

=4104+50

=4155

k nhak

1=???

2=(4x25)x37=100x37=3700

3=33750

4=28x(64+36)=28x100=2800

5=14386

6=810

7=(43x[42+57+1])-90=4300-90=4210

8=2772

a,4.37.25

=(4.25)+25

=100+25

=125

đó tui giải câu a thu

mấy câu khác dễ ợt

a) \(\left(42\times43+43\times57+43\right)-360:4\)

\(=43\times\left(42+57+1\right)-90\)

\(=43\times100-90\)

\(=4300-90\)

\(=4210\)

b) \(\left(372-19\times4\right)+\left(981:9-13\right)\)

\(=\left(4\times93-19\times4\right)+\left(109-13\right)\)

\(=4\times\left(93-19\right)+109-13\)

\(=4\times74+109-13\)

\(=296+109-13\)

\(=392\)

c) \(456:2\times18+456:3-102\)

\(=456\times\frac{1}{2}\times18+456\times\frac{1}{3}-102\)

\(=456\times\left(\frac{1}{2}\times18+\frac{1}{3}\right)-102\)

\(=456\times\left(9+\frac{1}{3}\right)-102\)

\(=456\times\frac{28}{3}-102\)

\(=4256-102\)

\(=4154\)

ko bk tính nhanh!

a)( 42 x 43 + 57+43 ) - 360 :4                                                 b) (372 - 19 x 4 ) + ( 981 : 9 - 13 )

  = 43 x (42 + 57 +1 ) - 90                                                       = (372 - 76 )  + ( 109 - 13) 

  = 43 x 100 - 90                                                                     = 296 + 96   

  = 4300 - 90                                                                          = 392   

  = 4210

a) 64.25+35.25+25

=25(64+35+1)=25.100=2500

b) 58.42+32.8+5.16

=2436+256+80=2772

c) (42.43+43.57+43)-360

=43(42+57+1)-360=43.100-360=4300-360=3940

Học tốt!

a) \(64\cdot25+35\cdot25+25=25\cdot\left(64+35+1\right)=2500\)

b) \(92\cdot42+32\cdot8+5\cdot16\)

\(=8\cdot21\cdot23+16\left(16+5\right)\)

\(=8\cdot21\cdot23+16\cdot21\)

\(=8\cdot21\cdot\left(23+2\right)\)

\(=8\cdot21\cdot25\)

\(=2\cdot21\cdot4\cdot25\)

\(=42\cdot100\)

\(=4200\)

c) \(\left(42\cdot43+43\cdot57+43\right)-360:4\)

\(=\left[43\cdot\left(42+57+1\right)\right]-360:4\)

\(=4300-90\)

\(=4210\)

phép tính này có quy tắc :

nhân chia trước, cộng trừ sau.

trong ngoặc trc ngoài ngoặc sau

tíc mình nha

(42 x 43 + 43 x 57 + 43) - 360 : 4

= 4426549 - 360 : 4

= 4426549 - 90

= 4426459

(372 - 19 x 4 +  (981 : 9 - 13)

= 296         +         96

= 392

456  : 2 x 18 + 456 : 3 - 102

= 4104         +             50

=  4154

>_< học tốt

372 - 19.4 + (981 : 9 - 13)

= 372 - 76 + (109 - 13)

= 296 + 96

=    392 

456:2×18+456:3-102

=228×18+(456:3)-102

=4164+152-102

=4154