Bài 1: 

\(101\cdot125+101\cdot25-101\cdot50\)

\(=101\cdot\left(125+25-50\right)\)

\(=101\cdot100\)

\(=10100\)

Bài 2: 

\(76\cdot115+56\cdot24+59\cdot24\)
\(=76\cdot115+24\cdot\left(56+59\right)\)

\(=76\cdot115+24\cdot115\)

\(=115\cdot\left(76+24\right)\)

\(=115\cdot100\)

\(=11500\)

5:

a: =>15x=165

=>x=11

b: =>x(x+1)/2=55

=>x^2+x=110

=>x=10

4: =>7x=56

=>x=8

Bài 1:

101•125+101•25+101•50

= 101•(125+25-50)

=101•100

=10100

Bài 2:

76•115+56•24+59•24

= 76•115+24•(56+59)

= 76•115+24•115

= 115•(76+24)

= 115•100

= 11500

Bài 1

a) \(5\times72\times10\times2=\left(5\times2\times10\right)\times72=100\times72=7200\) 

b) \(40\times125=5\times\left(8\times125\right)=5\times1000=5000\) 

c) \(16\times6\times25=4\times4\times6\times25=\left(4\times6\right)\times\left(4\times25\right)=24\times100=2400\) Bài 2:

a) \(24\times57+43\times24=24\times\left(57+43\right)=24\times100=2400\) 

b) \(12\times19+80\times12+12=12\times\left(19+80+1\right)=12\times100=1200\) 

c) \(\left(36\times15\times169\right)\div\left(5\times18\times13\right)\) 

 \(=\left(18\times2\times3\times5\times13\times13\right)\div\left(5\times18\times13\right)\) 

\(=\left(2\times3\times13\right)\times\left(18\times5\times13\right)\div\left(5\times18\times13\right)\) 

\(=2\times3\times13\)

\(=78\)

d) \(\left(44\times52\times60\right)\div\left(11\times13\times15\right)\) 

\(=\left(4\times11\times4\times13\times4\times15\right)\div\left(11\times13\times15\right)\)

\(=\left(4\times4\times4\right)\times\left(11\times13\times15\right)\div\left(11\times13\times15\right)\)

\(=4\times4\times4\)

\(=64\)

Bài 3:

a) \(x-280\div35=5\times54\) 

                \(x-8=270\) 

                      \(x=270+8\) 

                      \(x=278\) 

b) \(\left(x-280\right)\div35=54\div4\) 

    \(\left(x-280\right)\div35=\dfrac{27}{2}\) 

               \(x-280=\dfrac{27}{2}\times35\) 

                \(x-280=\dfrac{945}{2}\) 

                          \(x=\dfrac{945}{2}+280\) 

                          \(x=\dfrac{1505}{2}\) 

c) \(\left(x-128+20\right)\div192=0\) 

                 \(x-128+20=0\times192\) 

                \(x-128+20=0\) 

                        \(x-128=0-20\) 

                        \(x-128=-20\)

                                  \(x=-20+128\) 

                                 \(x=108\) 

d) \(4\times\left(x+200\right)=460+85\times4\) 

    \(4\times\left(x+200\right)=460+340\) 

    \(4\times\left(x+200\right)=800\) 

             \(x+200=800\div4\) 

             \(x+200=200\) 

                      \(x=200-200\) 

                      \(x=0\) 

Bài 4:

a) \(\dfrac{7}{12}-\dfrac{5}{12}=\dfrac{2}{12}=\dfrac{1}{6}\) 

b) \(\dfrac{8}{11}+\dfrac{19}{11}=\dfrac{27}{11}\) 

c) \(\dfrac{3}{8}+\dfrac{5}{12}=\dfrac{9}{24}+\dfrac{10}{24}=\dfrac{19}{24}\) 

d) \(\dfrac{3}{4}+\dfrac{7}{12}=\dfrac{9}{12}+\dfrac{7}{12}=\dfrac{16}{12}=\dfrac{4}{3}\) 

Bài 5:

a) \(x-\dfrac{6}{7}=\dfrac{5}{2}\) 

           \(x=\dfrac{5}{2}+\dfrac{6}{7}\) 

           \(x=\dfrac{47}{14}\) 

b) \(\dfrac{12}{7}\div x+\dfrac{2}{3}=\dfrac{7}{5}\) 

            \(\dfrac{12}{7}\div x=\dfrac{7}{5}-\dfrac{2}{3}\) 

             \(\dfrac{12}{7}\div x=\dfrac{11}{15}\) 

                       \(x=\dfrac{12}{7}\div\dfrac{11}{15}\) 

                        \(x=\dfrac{180}{77}\)

`@` `\text {Ans}`

`\downarrow`

`1,`

`a)`

`5 \times 72 \times 10 \times 2`

`= 5 \times 2 \times 10 \times 72`

`= 10 \times 10 \times 72`

`= 100 \times 72`

`= 7200`

`b)`

`40 \times 125`

`= 4 \times 10 \times 25 \times 5`

`= (5 \times 10) \times (4 \times 25)`

`= 50 \times 100`

`= 5000`

`c)`

`4 \times 2021 \times 25`

`= (4 \times 25) \times 2021`

`= 100 \times 2021`

`= 202100`

`d)`

`16 \times 6 \times 25`

`= 4 \times 4 \times 6 \times 25`

`= (4 \times 25) \times 4 \times 6`

`= 100 \times 24`

`= 2400`

`2,`

`a)`

`24 \times 57 + 43 \times 24`

`= 24 \times (57+43)`

`= 24 \times 100`

`= 2400`

`b)`

`12 \times 19 + 80 \times 12 +12`

`= 12 \times (19 + 80 + 1)`

`= 12 \times 100`

`= 1200`

`c)`

`(36 \times 15 \times 169) \div (5 \times 18 \times 13)`

`= 36 \times 15 \times 169 \div 5 \div 18 \div 13`

`= 6 \times 6 \times 3 \times 5 \times 13 \times 13 \div 5 \div 3 \times 6 \div 13`

`= (6 \div 6) \times (3 \div 3) \times (5 \div 5) \times (13 \div 13) \times 6 \times 13`

`= 6 \times 13`

`= 78`

`d)`

`(44 \times 52 \times 60) \div ( 11 \times 13 \times 15)`

`= 44 \times 52 \times 60 \div 11 \div 13 \div 15`

`= 4 \times 11 \times 13 \times 4 \times 15 \times 4 \div 11 \div 13 \div 15`

`= (11 \div 11) \times (13 \div 13) \times (15 \div 15) \times 4 \times 4 \times`

`= 4 \times 4 \times 4`

`= 64`

`3,`

`a)`

`x - 280 \div 35 = 5 \times 54`

`x - 8 = 270`

`x = 270 + 8`

`x = 278`

`b)`

`(x - 280) \div 35 = 54 \div 4`

`(x - 280) \div 35 = 13,5`

`x - 280 = 13,5 \times 35`

`x - 280 = 472,5`

`x = 472,5 + 280`

`x = 752,5`

`c)`

`(x - 128 + 20) \div 192 = 0`

`x - 128 + 20 = 0 \times 192`

`x - 128 + 20 = 0`

`x - 108 = 0`

`x = 0 + 108`

`x = 108`

`d)`

`4 \times (x + 200) = 460 + 85 \times 4`

`4 \times (x+200) = 460 + 340`

`4 \times (x+200) = 800`

`x + 200 = 800 \div 4`

`x + 200 = 200`

`x = 200 - 200`

`x = 0`

`4,`

`a)`

`7/12 - 5/12`

`= (7 - 5)/12`

`= 2/12`

`= 1/6`

`b)`

`8/11 + 19/11`

`= (8+19)/11`

`= 27/11`

`c)`

`3/8 + 5/12`

`= 9/24 + 10/24`

`= 19/24`

`d)`

`3/4 + 7/12`

`= 9/12 + 7/12`

`= 16/12`

`= 4/3`

`5,`

`a)`

`x - 6/7 = 5/2`

`x = 5/2 + 6/7`

`x = 47/14`

`b)`

`12/7 \div x + 2/3 = 7/5`

`12/7 \div x = 7/5 - 2/3`

`12/7 \div x = 11/15`

`x = 12/7 \div 11/15`

`x = 180/77`

`@` `\text {Kaizuu lv uuu}`

a, => x-13 = 184 : 8 = 23

=> x = 23 + 13 = 36

b, => x : 7 = 833 : 7 = 119

=> x = 119 x 7 = 833

c, => x+5 = 729 : 9 = 81

=> x = 81 - 5 = 76

d, => 50 - (17-x) = 36

=> 17-x = 50 - 36 = 14

=> x = 17 - 14 = 3

Tk mk nha

a)(x-13)*8=184

x-13=184:8

x-13=23

x=23+13

x=36

b)7*(x:7)=833

x:7=833:7=119

x=119*7=833

Chỉ làm thế thôi , làm tiếp

Trả lời :

a, ( x - 13 ) . 8 = 184

=> x - 13 = 184 : 8

x - 13 = 23

x = 23 + 13

x = 36

b, 7 . ( x : 7 ) = 833

=> x : 7 = 833 : 7

x : 7 =  119

x = 119 x 7

x = 833

c, 9 . ( x + 5 ) = 729

=> x + 5 = 729 : 9

x + 5 = 81

x = 81 - 5

x = 76

d, 1200 : 24 - ( 17 - x ) = 36

=> 50 - ( 17 - x ) = 36

=> 17 - x = 50 - 36

17 - x = 14

=> x = 17 - 14

x = 3

Vậy x = ..............( bạn tự đáp số nha!)^_@

bn ơi là bằng 0 nhé

nhớ cho mik điêm nhé

mk chi chep thua so thu 3 thoi nhe con 2 thua so con lai giu nguyen

42/30.75/23-19/23.210/38

=7/5.75.1/23-1/23.19.210/38

=7.15.1/23-1/23.210/2

=105.1/23-1/23.105=0

gia tri bieu thuc=0
 

a, x-13=184:8

x-13=23

x=23+13

x=36

Vậy x=36

b,x:7=833:7

x:7=119

x=119x7

x=833

Vậy x=833

c, x+5=729:9

x+5=81

x=81-5

x=76

Vậy x=76

d,50-(17-x)=36

17-x=50-36

17-x=14

x=17-14

x=3

Vậy x=3

Hok tốt

\(\frac{x+24}{1996}+\frac{x+25}{1995}+\frac{x+26}{1994}+\frac{x+27}{1993}+\frac{x+2036}{4}=0\\ \Leftrightarrow\left(\frac{x+24}{1996}+1\right)+\left(\frac{x+25}{1995}+1\right)+\left(\frac{x+26}{1994}+1\right)+\left(\frac{x+27}{1993}+1\right)+\left(\frac{x+2036}{4}-4\right)=0\\ \Leftrightarrow\frac{x+2020}{1996}+\frac{x+2020}{1995}+\frac{x+2020}{1994}+\frac{x+2020}{1993}+\frac{x+2020}{4}=0\\ \Leftrightarrow\left(x+2020\right)\left(\frac{1}{1996}+\frac{1}{1995}+\frac{1}{1994}+\frac{1}{1993}+\frac{1}{4}\right)=0\\\Leftrightarrow x+2020=0\\\Leftrightarrow x=-2020\)

Vậy pt có tập nghiệm \(S=\left\{-2020\right\}\)

\(\Leftrightarrow\frac{x+24}{1996}+1+\frac{x+25}{1995}+1+\frac{x+26}{1994}+1+\frac{x+27}{1993}+1+\frac{x+2036}{4}-4=0\)

\(\Leftrightarrow\left(x+2020\right)\left(...\right)=0\Rightarrow x=-2020\)

Bài 1:

A =  1996 x 1997 x 1998 x 1999 + 2021 x 2022 x 2023 x 2024

A = (1996 x 1997) x (1998  x 1999) + (2021 x 2022) x (2023 x 2024)

A = \(\overline{..2}\) x \(\overline{..2}\) + \(\overline{..2}\) x \(\overline{..2}\)

A = \(\overline{..4}\) + \(\overline{..4}\)

A = \(\overline{..8}\)