\(24\cdot76+48\cdot12-20\cdot100=24\cdot76+24\cdot2\cdot12-20\cdot100\)

                                                     \(=24\cdot\left(76+2+12\right)-20\cdot100\)

                                                     \(=24\cdot100-20\cdot100\)

                                                     \(=\left(24-20\right)\cdot100\)

                                                     \(=4\cdot100=400\)

Cảm ơn bạn nhiều nha

24 x 76  + 48 x 12 - 20 x 100

= 12 x 2 x 76 + 48 x 12 - 20 x 100

= 24 x ( 76 + 48 + 12 ) - 20 x 100

= 24 x 100 - 20 x 100

= ( 24 - 20 ) x 100

= 4 x 100

= 400

\(=20,15\times\left(23+76+1\right)=20,15\times100=2015\)

=20,15x(23+76+1)

=20,15x100

=2015

Đây nha

=20,15x(23+76+1)

=20,15x100=2015

Đáp án:

12 + 24 + 88 + 76 + 10

= ( 12 + 88 )  + ( 24 + 76)

=       100         +       100

= 200

\(a,2\times31\times12+4\times6\times42+8\times27\times3\)

\(=24\times31+24\times42+24\times27\)

\(=24\times\left(31+42+27\right)\)

\(=24\times100\)

\(=2400\)

\(b,583.931+69.\left(170+583\right)+31.170\)

\(=583.931+69.170+69.583+31.170\)

\(=583.\left(931+69\right)+170.\left(69+31\right)\)

\(=583.1000+170.100\)

\(=583000+17000\)

\(=600000\)

\(c,732.976+24.\left(680+732\right)+76.680\)

\(=732.976+24.680+24.732+76.680\)

\(=732.\left(976+24\right)+680.\left(24+76\right)\)

\(=732.1000+680.100\)

\(=732000+68000\)

\(=800000\)

Học tốt

a)2400

b)600000

c)800000

a) 2 x 31 x 12 + 4 x 6 x 42 + 8 x 27 x 3

= 24 x 31 + 24 x 42 + 24 x 27

= 24 x ( 31 + 42 + 27 )

= 24 x 100

= 2400

b) 583 x 931 + 69 x ( 170 + 583 ) + 31 x 170

= 583 x 931 + 69 x 170 + 69 x 583 + 31 x 170

= 583 x ( 931 + 69 ) + 170 x ( 69 + 31 )

= 583 x 1000 + 170 x 100

= 583000 + 17000

= 600000

c) 732 x 976 + 24 x ( 680 + 732 ) + 76 x 680

= 732 x 976 + 24 x 680 + 24 x 732 + 76 x 680

= 732 x ( 976 + 24 ) + 680 x ( 24 + 76 )

= 732 x 1000 + 680 x 100

= 732000 + 68000

= 800000

b) 35 x 24 + 35 x 76 +55 x 19 +55 x 91

= 35 x ( 24 + 76 ) + 55 x ( 19 + 91 )

= 35 x100 +55 x 100

= 100 x ( 55 + 35 )

= 90 x 100 =9 000

c) \(6\cdot25\cdot4+4\cdot19\cdot6-2\cdot14\cdot12\)

\(=24\cdot25+24\cdot19-24\cdot14\)

\(=24\left(25+19-14\right)\)

\(=24\cdot30=720\)

d) \(19\cdot64+76\cdot34\)

\(=76\cdot19+76\cdot34\)

\(=76\left(19+34\right)=76\cdot53=4028\)

a) 2 x 16 x 50 x 25

= ( 2 x 50 ) x ( 16 x 25 )

= 100 x 400 

= 40 000

  3x8x76+2x35x12-4x11x6

= 24x76+24x35-24x11

= 24x(76+35-11)

=24x100

= 2400

3 x 8 x  76 + 2 x 35 x 12 - 4 x 11 x 6

= ( 3 + 2 ) x ( 8 + 35 ) x ( 76 + 12 )  - 4 x 11 x 6

= 5 x 43 x 88 - 4x 11 x 6

= ( 5-4 ) x ( 43 - 11 ) x ( 88 - 6 )

= 1 x 32 x 82

= 2624

3.8.76+2.35.12-4.11.6

=1824+840-264

=2664-264

=2400

1a) -54 . 76 + 12 .(-76) + 76.(-34)

= (-54 - 12 - 34).76

= -100 . 76

= -176

b) 37.(63 - 24) - 63.(24 + 37)

= 37 . 63 - 37 . 24 - 63.24 - 63 . 37

= (37.63 - 63.37) - (37 + 63) . 24

= 0 - 100 . 24

= - 2400

2a) x + (-27) = -23 - x

=> x + x = -23 + 27

=> 2x = 4

=> x = 4 : 2

=> x = 2

b) xy + 2x - y = 15

=> x(y + 2) - y = 15

=> x(y + 2) - (y + 2) = 13

=> (x - 1)(y + 2) = 13 = 1 . 13 = 13 . 1

Lập bảng :

Vậy ...

\(24.17+52.76+24.35\)

\(=24.\left(17+35\right)+52.76\)

\(=24.52+52.76\)

\(=52.\left(76+24\right)\)

\(=52.100\)

\(=5200\)

   24 x 17 + 52 x 76 + 24 x 35

= 24 x ( 17 + 35 ) + 52 x 76

= 24 x 52 + 52 x 76

= 52 x ( 24 + 76 )

= 52 x 100

= 5200

         ~~~~~~~~~~Hok tốt~~~~~~~~~~

  24 x 17 + 52 x 76 + 24 x 35 

=24 x 17 + 52 x 3 x 24 + 24 x 35

=24 x 17 + 156 x 24 + 24 x 35

=24 x (17 + 156 + 35)

=24 x 208

=4932

đó là cách nhanh nhất

`@` `\text {Ans}`

`\downarrow`

`A)`

`37 \times 46+37 \times 51+111`

`= 37 \times (46+51)+111`

`= 37 \times 97+111`

`= 3589 +111`

`= 3700`

`B)`

`35 \times 215-35 \times 210-175`

`= 35 \times (215-210)-175`

`= 35 \times 5-175`

`= 175-175=0`

`E)`

`76 \times 102-76 \times 2`

`= 76 \times (102-2)`

`= 76 \times 100`

`= 7600`

`C)`

`85 \times 94+85 \times 2 +170 \times 2`

`= 85 \times (94+2) + 170 \times 2`

`= 85 \times 96+170 \times 2`

`= 8160+340`

`= 8500`

`48 \times 56+28 \times 104`

`= 48 \times 28 \times 2+28 \times 104`

`= 28 \times (48 \times 2+104)`

`= 28 \times (96+104)`

`= 28 \times 200`

`= 5600`

`G)`

`206 \times 12-206-206`

`= 206 \times (12-1-1)`

`= 206 \times 10`

`= 2060`

a) 37 x 46 + 37 x 51 + 111

= 37 x ( 46 + 51 ) + 111

= 37 x 97 + 111

= 3589 + 111

= 3700

b) 35 x 215 - 35 x 210 - 175

= 35 x ( 215 - 210 ) - 175

= 35 x 5 - 175

= 175 - 175

= 0

e) 76 x 102 - 76 x 2

= 76 x ( 102 - 2 )

= 76 x 100

= 7600

c) 85 x 94 + 95 x 2 + 170 x 2

= 7990 + 2 x ( 95 + 170 )

= 7990 + 2 x 265

= 7990 + 530

= 8520

48 x 56 + 28 x 104

= 2688 + 2912

= 5600

g) 206 x 12 - 206 - 206

= 2472 - 206 - 206

= 2266 - 206

= 2060