\(\left(19\frac{5}{8}:\frac{7}{12}-13\frac{1}{4}:\frac{7}{12}\right).\frac{4}{5}\)

\(=\left(\frac{157}{8}:\frac{7}{12}-\frac{53}{4}:\frac{7}{12}\right).\frac{4}{5}\)

\(=\left[\left(\frac{157}{8}-\frac{53}{4}\right):\frac{7}{12}\right].\frac{4}{5}\)

\(=\left[\frac{51}{8}:\frac{7}{12}\right].\frac{4}{5}\)

\(=\frac{153}{14}.\frac{4}{5}\)

\(=\frac{306}{35}\)

\(\left(\frac{-2}{5}+\frac{3}{7}\right)-\left(\frac{4}{9}+\frac{12}{20}-\frac{13}{35}\right)+\frac{7}{35}\)

\(=\frac{1}{35}-\frac{212}{315}+\frac{7}{35}\)

\(=\frac{1}{35}+\frac{-212}{315}+\frac{7}{35}\)

\(=\frac{9}{315}+\frac{-212}{315}+\frac{63}{315}\)

\(=\frac{-140}{315}=\frac{-4}{9}\)

\(\left(4\frac{5}{57}-3\frac{4}{51}+8\frac{13}{29}\right)-\left(3\frac{5}{57}-6\frac{16}{29}\right)\)

\(=\left(\frac{233}{57}-\frac{157}{51}+\frac{245}{29}\right)-\left(\frac{176}{57}-\frac{190}{29}\right)\)

\(=\frac{1941}{323}-\frac{-5726}{1653}\)

\(=\frac{14011}{1479}\)

`#3107.101107`

`1)`

`58 + 7x = 100`

`=> 7x = 100 - 58`

`=> 7x = 42`

`=> x = 42 \div 7`

`=> x = 6`

Vậy, `x = 6`

`2)`

`(x - 12) \div 12 = 12`

`=> x - 12 = 12*12`

`=> x - 12 = 144`

`=> x = 144 + 12`

`=> x = 156`

Vậy, `x = 156`

`3)`

`x - 56 \div 4 = 16`

`=> x - 14 = 16`

`=> x = 16 + 14`

`=> x = 30`

Vậy, `x = 30`

`4)`

`101 + (36 - 4x) = 105`

`=> 36 - 4x = 105 - 101`

`=> 36 - 4x = 4`

`=> 4x = 36 - 4`

`=> 4x = 32`

`=> x = 32 \div 4`

`=> x = 8`

Vậy, `x = 8`

`5)`

`2(x - 51) = 2*2^3 + 20`

`=> 2(x - 51) = 2^4 + 20`

`=> 2(x - 51) = 16 + 20`

`=> 2(x - 51) = 36`

`=> x - 51 = 36 \div 2`

`=> x - 51 = 18`

`=> x = 18 + 51`

`=> x = 69`

Vậy, `x = 69.`

1) 58 + 7x=100

             7x = 100 - 58

             7x = 42

              x = 42 : 7

              x = 6

2)(x-12):12=12

    (x - 12) = 12 x 12

    x - 12   = 144

     x          = 144 + 12

      x =  156

3)x-56:4=16

   x - 14 = 16

    x       = 16 + 14

    x       = 30

4) 101+(36-4x)=105

             (36-4x) = 105 - 101

              36-4x  =   4

                     4x = 36 - 4

                      4x = 32

                        x = 32 : 4

                        x = 8

5)2(x-51)=2.2 mũ 3 + 20

    2(x-51)=2.8 + 20

     2(x-51)=16 + 20

     2(x-51)= 36

        x - 51 = 36 : 2

         x - 51 = 18

         x = 18 + 51

         x = 69

1: 7x+58=100

=>\(7x=100-58=42\)

=>\(x=\dfrac{42}{7}=6\)

2: \(\left(x-12\right):12=12\)

=>\(x-12=12\cdot12=144\)

=>x=156

3: \(x-56:4=16\)

=>\(x-14=16\)

=>x=30

4: \(101+\left(36-4x\right)=105\)

=>36-4x=4

=>4x=32

=>x=8

5: \(2\cdot\left(x-51\right)=2\cdot2^3+20\)

=>\(2\left(x-51\right)=16+20=36\)

=>x-51=18

=>x=69

208 - 84: 12= 208- 7= 201

5^6 : 5^3 + 2^3.2^2= 5^3 + 2^5= 125 + 32= 1577

15 . 2^3 + 4 . 3^2 - 5.7= 15 . 8 + 4. 9 - 5.7= 120 + 36 - 35=156 - 35=121

164 . 53 + 47 . 164= 164.(53 + 47)=164. 100=16400

a)204-84:12=204-7=197

b)5⁶:5³+2³.2²=(5:5)⁹+2⁵=9+32=41       

c)15.2³+4.3²-5.7=15.8+4.9-35=120+36-35=121

d)164.53+47.164=(53+47).164=100.164=16400

`@` `\text {Ans}`

`\downarrow`

`1)`

`5/7*37 13/23 - 51 13/23*5/7`

`= 5/7* (37 13/23 - 51 13/23)`

`= 5/7* (-14)`

`= -10`

`2)`

`-2/3 +1/3+0,5+2 1/2`

`= -2/3 + 1/3 + 1/2 + 5/2`

`= (-2/3+1/3) + (1/2+5/2)`

`= -1/3 + 3`

`=8/3`

`3)`

`-0,5+2/3+1/2`

`= -1/2 + 2/3 + 1/2`

`= (-1/2 + 1/2) + 2/3`

`= 2/3`

`4)`

`(8+2 1/3-3/5) -(5+0,4)-(3 1/2 -2)`

`= 8+ 7/3 - 3/5 - 5 - 0,4 - 7/2 + 2`

`= (8+2-5) + (-3/5 - 2/5) + (7/3 - 7/2)`

`= 5 - 1 - 7/6`

`= 4 - 7/6 = 17/6`

`5)`

`(2/9-7/12):3/4+(16/9-5/12):3/4`

`= (2/9 - 7/12) \times 4/3 + (16/9 - 5/12) \times 4/3`

`= 4/3 *(2/9 - 7/12 + 16/9 - 5/12)`

`= 4/3 * [(2/9 + 16/9) + (-7/12 - 5/12)]`

`= 4/3 * ( 2 - 1)`

`= 4/3 * 1 = 4/3`

`6)`

`-(2021.0,7+19,75) +0,7- (8-19,75)`

`= -2021*0,7 -19,75 + 0,7 - 8 + 19,75`

`= 0,7*(-2021 + 1) - 8`

`= -1414-8`

`= -1422`

`7)`

`15/34+7/21+19/34-20/15`

`= (15/34 + 19/34) + 7/21 - 20/15`

`= 1 + 7/21 - 20/15`

`= 4/3 - 20/15 =0`

`8)`

`2 5/6+1/6:(-5/8)`

`= 17/6 + (-4/15)`

`= 77/30`

`9)`

`(-2)^2 +2/9. (4/5-2/3)`

`= 4 + 2/9*2/15`

`= 4+4/135`

`= 544/135`

`10)`

`(-1/5+3/7):5/4+(-4/5+4/7):5/4`

`= (-1/5+3/7) * 4/5 + (-4/5+4/7) * 4/5`

`= 4/5*(-1/5 +3/7-4/5+4/7)`

`= 4/5*[(-1/5-4/5)+(3/7+4/7)]`

`= 4/5* (-1+1)`

`= 4/5*0=0`

`11)`

`2022,2021 . 1954,1945+ 2022,2021 . (-1954,1945)`

`= 2022,2021 * [1954,1945 + (-1954,1945)]`

`= 2022,2021*0 `

`= 0`

`12)`

`-5,2 .72 +69,1 +5,2 . (-28)+(-1,1)`

`= -5,2*72 + 69,1 - 5,2*28 - 1,1`

`= -5,2*(72+28) + (69,1 - 1,1)`

`= -5,2*100 + 68`

`= -520 + 68`

`= -452`

`13)`

`(7 -1/2-3/4) : (5-1/4-5/8)`

`= 23/4 \div 33/8`

`=46/33`

`14)`

`(8+ 2 1/3 -3/5) -(5+0,4) -( 3 1/3 - 2)`

`= 8+ 2 1/3 - 3/5 - 5 - 0,4 - 3 1/3 + 2`

`= (8+2-5) + (2 1/3 - 3 1/3) - (0,6 + 0,4) `

`= 5 - 1 - 1`

`= 3`

help lười tính quá

2: \(=\dfrac{-1}{3}+3=\dfrac{8}{3}\)

3: =1/2-1/2+2/3=2/3

5: \(=\dfrac{4}{3}\left(\dfrac{2}{9}-\dfrac{7}{12}+\dfrac{16}{9}-\dfrac{5}{12}\right)=\dfrac{4}{3}\)

12: \(=5.2\left(-72-28\right)+68=-520+68=-452\)

13: \(\dfrac{23}{4}:\dfrac{33}{8}=\dfrac{46}{33}\)

Bài 2. > , < ,  = ?

5/7 < 4/3             2/5 < 6/10            1/4 = 3/12                27/36 >

2/9           7/6 > 7/9

7/2 = 2/7        15/23 < 1                  27/9 > 2          14/15 < 1          51/17 < 4

sai rôi

a, - 51-(-12) + (-4)

= -51+12-4

= - (51-12) -4

= ( -39) -4

= (-39)+ (-4)

= -43

Đây là câu a

a . -43

b. -17

c. -4

d.132 ( tui tính vậy)

b, -5-(+7)+3+(-8)

= -5+7+3-8

 =-5+7+3+(-8)

= (-5+-8)+(7+3)

= -13+10

= -3

Câu b nè bạn