\(a)4567+1234-4567-4\)

\(=4567-4567+1234-4\)

\(=0+1230=1230\)

\(b)2001-53-1519-\left(-53\right)\)

\(=2001-53-1519+53\)

\(=2001-1519-53+53\)

\(=482\)

\(c)35-17-2017-35-\left(-2017\right)\)

\(=35-35-2017+2017-17\)

\(=0-0-17=-17\)

a. 4567+(1234-4567)-4

=4567+1234-4567-4

=(4567-4567)+(1234-4)

=0+1230

=1230

2001-( 53 -1579 ) - ( - 53 )

=2001-53+1579+53

=(2001+1579)+(53-53)

=3580+0

=3580

35-17 + 2017 - 35 + ( -2017 )

=35-17+2017-35-2017

=(35-35)+(2017-2017)-17

=0+0-17

=-17

a) 4567 + ( 1234 - 4567 ) - 4

= 4567 + 1234 - 4567 - 4

= ( 4567 - 4567 ) + ( 1234 - 4 )

= 0 + 1230

= 1230

b) 2001 - ( 53 - 1579 ) - (-53)

= 2001 - 53 + 1579 + 53

= ( 2001 + 1579 ) - ( 53 - 53 )

= 3580 - 0

= 3580

c) 35 - 17 + 2017 - 35 + (-2017)

= 35 - 17 + 2017 - 35 - 2017

= ( 35 - 35 ) - 17 + ( 2017 - 2017 )

= 0 - 17 + 0

= -17 

\(a)4567+1234-4567-4\)

\(=\left(4567-4567\right)+\left(1234-4\right)=0+1230=1230\)

Bài toán 1 : Tìm x nguyên biết.

a. 3 ≤ x – 2 < 5

=>3-2 < x-2 < 5-2

=>1 < x < 3

=>x=1

Vậy x=1

b. 0 ≤ x – 5 ≤ 2

=>0-5 < x-5 < 2-5

=>-5 < x < -3

=>x=-4

Vậy x=-4

Bài toán 2 : Tính hợp lý.

a. 4567 + (1234 – 4567) -4

=4567+1234-4567-4

=(4567-4567)+(1234-4)

=0+1230

=1230

b. 2001 – (53 + 1579) – (-53)

=2001-53-1579+53

=(2001-1579)+(-53+53)

=422+0

=422

c. 35 – 17 + 2017 – 35 + (-2017)

=(35-35)+[2017+(-2017)]-17-35

=0+0-17-35

=0-17-35

=-52

d. 37 + (-17) – 37 + 77

=(37-37)+[-17+77]

=0+60

=60

e. –(-219) + (-219) – 401 + 12

=0-401+12

=-389

f. |-85| – (-3).15

=85+3.15

=85+45

=130

g. 11.107 + 11.18 – 25.11

=11.(107+18-25)

=11.100

=1100

h. 115 – (-85) + 53 – (-500 + 53)

=115+85+53+500-53

=(53-53)+(115+85+500)

=0+700

=700

k. (-18) + (-31) + 98 + |-18| + (-69)

=-18-31+98+18-69

=(-18+18)+(-31-69)+98

=0+(-100)+98

=-100+98

=-2

Bài toán 4 : Tìm x, biêt.

a. 5x – 16 = 40 + x

    5x - x = 40 + 16

    4x = 56

      x = 56 : 4

      x=14

b. 4x – 10 = 15 – x

    4x + x = 15 + 10

    5x = 25

      x = 25 : 5

      x = 5

c. -12 + x = 5x – 20

    -12 + 20 = 5x - x

          8 = 4x

          x = 8 : 4

          x = 2

d. 7x – 4 = 20 + 3x

    7x - 3x = 20 + 4

    4x=24

      x=24:4

      x=6

e. 5x – 7 = – 21 – 2x

    5x + 2x = -21+7

    7x = -14

      x = -14 : 7

      x = -2

f. x + 15 = 7 – 6x

   x + 6x = 7 - 15

   7x = -8

     x = -8/7

g. 17 – x = 7 – 6x

    17 - 7 = -6x + x

    10 = -7x

      x=10/-7

h. 3x + (-21) = 12 – 8x

    3x + 8x = 12 + 21

    11x = 33

        x = 33:11

        x=3 

k. 125 : (3x – 13) = 25

3x-13=125:25

3x-13=5

3x=5+13

3x=18

  x=18:3

  x=6

l. 541 + (218 – x) = 735

  218-x=735-541

  218-x=693

         x=218-693

         x=-475

\(1)5-(1997-2005)+1997\)

\(=5-1997+2005+1997\)

\(=(-1997+1997)+(5+2005)\)

\(=0+2010\)

\(=2010\)

\(2)4567+(1234-4567)-4\)

\(=4567+1234-4567-4\)

\(=(4567-4567)+(1234-4)\)

\(=0+1230\)

\(=1230\)

dễ mà :  a, 5 - ( 1997 - 2005 ) +1997

= ( 2005 + 5 ) - ( 1997 - 1997 )

= 2010 - 0

= 2010

a, 5  - (1997 -2005 ) + 1997 

= 5 - 1997 + 2005 +1997

=  (5 + 2005 ) - ( 1997 - 1997)

= 2010 - 0 

= 2010

b, 4567 + (1234 - 4567 )-4

=  4567  + 1234 - 4567  -4

= (4567 - 4567 ) + (1234 - 4)

= 0 + 1230 

= 1230 

c, 173 - ( 36 + 173 ) + [(175 - 27 ) - 175 - ( -36 + 50 )]

= 173 - 36 - 173 + 175 - 27 - 175 - 36 - 50 

= ( 173 - 173 ) + (175 - 175 ) - ( 36 + 36 ) - (27 + 50)

= 72 - 77 

= -5

d, 3 . (25 : 5 - 14 : 2 ) - 5 . ( 6 : 2)

= 3  (-2)  - 5 .3

= 3 ( -2 - 5 )

= 3 . (-7 )

= - 21

a) 5-(1997-2005)+1997

= 5-(-1997)+2005+1997

= (5+2005)+(-1997+1997)

= 2010+0

= 0

b) 4567+(1234-4567)-4

 làm tương tự câu a

a,3/7 +1/2-[-3]/70

=13/14 -[-3]/70

=65/70 -[-3]/70

=34/35

b,3/5+-1/25 -35/100

=14/25 - 35/100

=56 /100 -35/100

= 21/100

c ,5/12 -3/-16+3/4

=29/48 +3/4

= 29/48 +36/48

=65/48

d, 5/15 +4/-12 +1/7 -1/-6

= 1/3 +1/-3 +1/7-1/-6

=0+1/7-1/-6

= 13/42

A.\(\dfrac{3}{7}+\dfrac{1}{2}+\dfrac{\left(-3\right)}{70}\)

=\([\dfrac{30}{70}+\dfrac{\left(-3\right)}{70}]\)+\(\dfrac{1}{2}\)

= \(\dfrac{27}{70}+\dfrac{35}{70}\)

=\(\dfrac{62}{70}=\dfrac{31}{35}\)

B.\(\dfrac{3}{5}+\dfrac{-1}{25}-\dfrac{35}{100}\)

=\(\dfrac{60}{100}+\dfrac{-4}{100}-\dfrac{35}{100}\)

=\(\dfrac{60+\left(-4\right)-35}{100}\)

=\(\dfrac{21}{100}\)

C.\(\dfrac{5}{12}-\dfrac{3}{-16}+\dfrac{3}{4}\)

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

=\(\dfrac{7}{6}-\dfrac{-3}{16}\)

=\(\dfrac{56}{48}-\dfrac{-9}{48}\)=\(\dfrac{65}{48}\)

D.\(\dfrac{5}{15}+\dfrac{4}{-12}+\dfrac{1}{7}-\dfrac{1}{-6}\)

=\(\dfrac{1}{3}+\dfrac{1}{7}+(\dfrac{-2}{6}-\dfrac{-1}{6})\)

=\(\dfrac{1}{3}+\dfrac{1}{7}+\dfrac{-1}{6}\)

=\((\dfrac{1}{3}+\dfrac{-1}{6})+\dfrac{1}{7}\)

=\(\dfrac{1}{6}+\dfrac{1}{7}\)=\(\dfrac{13}{42}\)

a, 4567 + ( 1234 - 4567 ) - 4 
= 4567 + 1234 - 4567 - 4
=(4567 - 4567) + (1234 - 4)
= 0 + 1230
=1230

b, 2001 - ( 53 + 1579 ) - ( - 53 )
= 2001 - 53 - 1579 + 53
=(2001-1579) - (53 - 53)
= 422 - 0
= 422

c, 79.89 - 79 . ( - 11 ) - 100.79 
= 79.(89 + 11 - 100)
= 79.0
= 0

d, 11.107 + 11.18 - 25.11 
= 11.(107 + 18 - 25)
= 11. 100
= 1100

e, -69 .|- 45 | -31 . | 45 |
= -69.45 - 31.45
= 45.(-69 - 31)
= 45.(-100)
= -4500

f, 17 . ( 15 - 16 ) + 16 
= 17.(15 - 16) + 17 - 1
= 17.(15 - 16 + 1) - 1
= 17.0 - 1
= -1

g, 37.24 + 37.76 + 63.79 + 21.63
= 37.(24 + 76) + 63.(79 + 21)
= 37.100 + 63.100
= 100.(37 + 63)
= 100.100
= 10000

h, 167 + ( - 252 ) + 52 + (- 67 )
= (167 - 67) - (252 - 52)
= 100 - 200
= -100

i, 118 + 107 - (- 118 - 93 ) - 58 
= 118 + 107 + 118 + 93 - 58
= (118 + 118 - 58) + (107 + 93)
= 178 + 100
= 278

k, 38 - 138 + 250 - 350 
= (38 - 138) + (250 - 350)
= -100 + (-100)
= -200

l, ( 139 - 172 + 99 ) - ( 139 + 199 - 172 ) 
= 139 - 172 +99 - 139 - 199 + 172
= (139 - 139) - (172 - 172) + (99 - 199)
= 0 - 0 + (-100)
= -100

m, mình không biết nhé :))) thông cảm

sửa lại câu i:
= 118 + 107 + 108 + 93 - 58
= (118 + 118 - 58) + (107 + 93)
= 178 + 200
= 378

mình có bổ xung câu h nha

167+(-252)+52+(-67)

=[167+(-67)] + [(-252)+52]

=    100        +     (-200)

=               -100