Đề trên lỗi nhé ae , đề đúng đây:

1. Tìm số đối của mỗi số nguyên sau: -7; 0; -4; 12; |-5|
và |5|.
2. Tính:
a) 8274 + 226 ;
b) (- 5 ) + ( -11) ; c) (- 43) + (-9)
3. Tính:
a) 17 + ( - 7) ;
b) (-96) + 64 ;
c) 75 + ( -325)
4. Tính:
a) 10- (-3) ;
b) (-21) – (-19);
c) 13 – 30 ;
d) 9 – (- 9)
5. Tính tổng:
a) (-30) + 15 + 10 + ( -15) ;
b) 17 + ( -12) + 25 – 17 ; b) 17 + ( -12) + 25 – 17 ;
c) (-14) + 250 + ( - 16) + (- 250) ;
d) ( -3) + ( - 14) + 27 + ( -10)

1. số đối: -7; 0; -4; 12; \(|-5|\); 5

là: 7; 0; 4; -12; -5; -5

2,3,4,a, 8274 + 226 = 8500

b, -5 + -11 = -16

c, -43 + -9 = -52

d, 17 + -7 = 10

e, -96 + 64 = -32

f, 75 + -325 = -250

g, 10 - (-3) = 10 + 3 = 13

h, -21 + 19 = -2

.., 13 - 30 = -17

.., 9 + 9 = 18

5, a,

-30 + 15 + 10 + -15 = -30 + 10 = 20

b, 17 + -12 + 25 - 17 = -12 + 25 = 13

c,-14 +250 - 16 - 250 = -14 + -16 = -30

d,-3 - 14 + 27 - 10 = 0

e, -14 + 250 - 16 - 250 = -14 + -16 = -30

f, -3 - 14 + 27 - 10 = 0

1) -39 +14+26+39

=   39-39 + 40

=40

2)  -54 +16 +(-6)+54

=54-54  +10

=10

3) 45 +23+(-35)+(-23)

=  45-35 +23 -23

=10+0

=10

4) 45  .17 - 5.9.7

=45.17 -45.7

=45.( 17-7)

=45 .10

=450

5) 24 ( 16-5) -16(24-5)

=24.16 -24.5 -16 .24 +16 .5

= 24.16 -16.24 +5 (16-24)

=0  +5 .(-8)

=-40

Chúc hok tốt!

1. ( - 39 ) + 14 + 26 + 39 

= [ ( - 39 ) + 39 ] + ( 14 + 26 )
= 0 + 40 

= 40

2. ( - 54 ) + 16 + ( - 6 ) + 54

= [ ( - 54 ) + 54 ] + [ 16 + ( - 6 ) ]

= 0 + 10

= 10

3. 45 + 23 + ( - 35 ) + ( - 23 )

= [ 45 + ( - 35 ) ] + [ 23 + ( - 23 ) ] 

= 10 + 0 

= 10

4. 45 . 17 - 5 . 9 . 7

= 45 . 17 - 45 . 7 

= 45 . ( 17 - 7 )
= 45 . 10

= 450

5. 24 . ( 16 - 5 ) - 16 . ( 24 - 5 )

= 24 . 11 - 16. 19

= 264 - 304

= 264 + ( - 304 )

= - ( 304 - 364 ) 

= - 40

Chúc bạn học tốt ! 

1. (-39)+14+26+39

\(=\left[\left(-39\right)+39\right]+\left(14+26\right)\)

\(=0+40\)

\(=40\)

2. (-54)+16+(-6)+54

\(=\left[\left(-54\right)+54+\left[16+\left(-6\right)\right]\right]\)

\(=0+10\)

\(=10\)

3. 45+23+(-35)+(-23)

\(=\left(45+\left(-35\right)\right)+\left(23+\left(-23\right)\right)\)

\(=10+0\)

\(=10\)

4. 45.17-5.9.7

\(=45.17-45.7\)

\(=45.\left(17-7\right)\)

\(=45.10\)

\(=450\)

5. 24.(16-5)-16.(24-5)

\(=24.16-24.5-16.24+16.5\)

\(=24.\left(16-16\right)+5.\left(-24+16\right)\)

\(=24.0+5.\left(-8\right)\)

\(=0+\left(-40\right)\)

\(=-40\)

a) 86 – 16 = 70 

b) 23 x 2 – 1 = 23 

c) 250 : 5 + 5 = 25 

d) 40 + 80 : 4 = 30 

e) 80 + 4 : 2 = 42 

f) 70 + 30 : 2 = 50 

g) 90 + 30 x 3 = 180 

h) 70 + 30 : 2 = 85 

1. -25.72 + 25.21 - 49.25

= 25.(-72) + 25.21 - 49.25

= 25.(-72 + 21 - 49)

= 25. (-100)

= -2500

2. 35(14 - 23) - 23(14 - 35)

= 35. (-9) - 23. (-9)

= -9(35 - 23)

= -9. 12

= -108

3. 8154 -(674 + 8154) + (-98 + 674)

= 8154 - 674 - 8154 + (-98) + 674

= 8154 - 8154 - 674 + 674 + (-98)

= -98

4. 25.21 + 25.72 + 49.25

= 25(21 + 72 + 49)

= 25. 142

= 3550

5. 27(13 - 16) - 16(13 - 27)

= (27.13 - 27.16) - (16.13 - 16.27)

= 27.13 - 27.16 - 16.13 - 16.27

= 27.13 - 16.13 - 27.16 - 16.27

= 27.13 - 16.13

= 13(27 - 16)

= 13.11

= 143

6. -1911 -(1234 - 1911)

= -1911 - 1234 + 1911

= -1911 + 1911 - 1234

= -1234

\(19+18+17+16+14+21+22+23+24+25+26\)

\(=\left(19+21\right)+\left(18+22\right)+\left(17+23\right)+\left(16+24\right)+\left(14+26\right)+25\)

\(=30+30+30+30+30+25\)

\(=175\)

\(\dfrac{1}{3}+\dfrac{1}{4}+\dfrac{1}{5}+\dfrac{4}{6}+\dfrac{9}{12}+\dfrac{16}{20}\)

\(=\dfrac{1}{3}+\dfrac{1}{4}+\dfrac{1}{5}+\dfrac{2}{3}+\dfrac{3}{4}+\dfrac{4}{5}\)

\(=\left(\dfrac{1}{3}+\dfrac{2}{3}\right)+\left(\dfrac{1}{4}+\dfrac{3}{4}\right)+\left(\dfrac{1}{5}+\dfrac{4}{5}\right)\)

\(\text{=}1+1+1\)

\(\text{=}3\)

1: Ta có: \(2155-\left(174+2155\right)+\left(-68+174\right)\)

\(=2155-174-2155-68+174\)

=-68

2) Ta có: \(-25\cdot72+25\cdot21-49\cdot25\)

\(=-25\cdot\left(72-21+49\right)\)

\(=-25\cdot100=-2500\)

câu nầy hơn khó nên mình ko giải đc bạn đợ mình giải đã

1) 2763 + 152 = 2951

2)(-7) + (-14) = -21

3)(-35) + (-9) =-44

4) (-5) + (-248) = -253