2020 x 14 + 4040 x 16 + 6060 x 18

= 2020 x 14 + 2020 x 2 x 16 + 2020 x 3 x 18

= 2020 x 14 + 2020 x 32 + 2020 x 54

= 2020 x (14 + 32 + 54)

= 2020 x 100

= 202000

\(2020\times14+4040\times16+6060\times18\)

\(=2020\times14+2020\times2\times16+2020\times3\times18\)

\(=2020\times14+2020\times32+2020\times54\)

\(=2020\times\left(14+32+54\right)\)

\(=2020\times100\)

\(=202000\)

202000

b,21/17x13/14x56x3/42

=21/17x3/42x56x13/14

=21x3/17x42 x 56x13/14

=21x3/17x21x2 x 14x4x13/14

=3/17x2 x 4x13

=3/24 x 52=3x52/24

=3x52/3x8

=52/8=13/2

a, 6/7 x 16/15 x 7/6 x 21/32

=(6/7 x 7/6)x16/15x21/32

=16/15x21/32

=16x21/15x32

=16x3x7/3x5x16x2

=7/5x2=7/10

2020*14+4040*16+6060*18

= 1010*2*14+1010*4*16+1010*6*18

=1010*28+1010*64+1010*108

=1010*(28+64+108)

=1010*200=202000

= 2020 * 14 + 2020 * 2 * 16 + 2020 * 3 * 18

= 2020 * 14 + 2020 * 32 + 2020 * 54

=2020 * (14 + 32 + 54)

=2020 * 100

=20200

cảm ơn bạn. bạn có thể giúp mình thêm 1 bài ko?

a) 142 x 12 + 42 x 18

= 142 x (12 +18)

= 142 x 30 = 4260

b) 49 x 365 - 39 x 365

= (49-39) x 365

= 10 x 365 = 3650

c) 4 x 18 x 25

= 18 x (4 x 25)

= 10 x 100 = 1800

a,=3/13.17/29.29/34

=3/13.1/2

=3/26

b,=(4/21+25/42).19/33

=11/14.19/33

=19/42

`a, = 3/13 xx (17/29 xx 29/34)`

`= 3/13 xx 1/2`

`= 3/26`.

`b, = 19/33(4/21 + 25/42)`

`= 19/33 xx ( 33/42 )`

`= 19/42`

`a)(3/13xx17/29)xx29/34=3/13xx17/29xx29/34=[3xx17xx29]/[13xx19xx17xx2]=3/26`

`b)4/21xx19/33+25/42xx19/33=19/33xx(4/21+25/42)=19/33xx(8/42+25/42)=19/33xx33/42=19/42`

313×1729)×2934(313×1729)×2934

=313×1729×2934=313×1729×2934

=3×17×2913×29×34=3×17×2913×29×34

=3×17×2913×29×2×17=3×17×2913×29×2×17

=313×2=313×2

=326=326

421×1933+2542×1933421×1933+2542×1933

=1933×(421+2542)=1933×(421+2542)

=1933×(842+2542)=1933×(842+2542)

=1933×3342=1933×3342

=19×3333×42=19×3333×42

=1942

   42 x 3 + 18 x 32 + 18 x 61

= 6 x 7 x 3 + 18 x 32 + 18 x 61

= 18 x 7 + 18 x 32 + 18  x 61

= 18 x (7 + 32 + 61)

= 18 x 100

= 1800

\(42\times3+18\times32+18\times61\)

\(=6\times7\times3+18\times32+18\times61\)

\(=18\times7+18\times32+18\times61\)

\(=18\times\left(7+32+61\right)\)

\(=18\times100\)

\(=1800\)

6 x 7 x 3 + 18 x 32 +18 x 61

18 x 7 + 18 x32 +18 x 61

18 x ( 7 + 32 + 61 )

18 x           100

1800

a﴿ ﴾46+2﴿x12:2 = 288

b﴿3,24x1,7+1,7x4,65‐13,78x0,85

= 1,7 x ﴾3,24+4,65﴿ ‐ 13,78x0,85

= 1,7 x 7,89 ‐ 11,713

= 13,413 ‐ 11,713

= 1,7 

a) (46+2)x12:2 = 288

b)3,24x1,7+1,7x4,65-13,78x0,85

= 1,7 x (3,24+4,65) - 13,78x0,85

= 1,7 x 7,89 - 11,713

= 13,413 - 11,713

= 1,7

a.

- Số số hạng là: (46-2):4+1=12 (số)

- Tổng số đầu và số cuối là: 46 + 2 = 48

- Tổng là: 12 x 48 : 2 = 288

b. 

3.24 x 1.7 + 1.7 x 4.65 - 13.78 x 0.85

= 3.24 x 1.7 + 1.7 x 4.65 - 6.89 x 1.7

= (3.24 + 4.65 - 6.89) x 1.7

= (7.89 - 6.89) x 1.7

= 1 x 1.7

= 1.7