7: =-1+8=7

6: \(=-\left(8\cdot125\right)\cdot\left(2\cdot5\right)\cdot\left(25\cdot4\right)=-1000000\)

5: =-50+19+143+79-25-48

=-75+98+95

=23+95

=118

4: =37x9+17x9-35x9-35x11

=18+153-385

=-214

3: =187-23-20+180

=367-43

=324

4: \(=37\cdot9+17\cdot9-35\cdot9-35\cdot11=19\cdot9-385\)

\(=171-385=-214\)

5: =-50+19+143+79-25-48

=-75+94+95

=20+94

=114

3 ; 324

4 ; -214

5 ; 118

6 ; - 1 000 000

7 ; 7

học tốt

1) 125.(-24) + 24.225.

\(=24\left(-125+225\right)=24.100=2400.\)

2) 512.(2 – 128) – 128. (-512).

\(=512\left(2-128+128\right)=512.2=1024.\)

a) ( -125) + 100 + 80 + 125 + 20

= [ ( -125)+125] + ( 80+20) + 100

= 0 + 100 + 100 = 200

b) 27 + 55 + (-17) + ( - 55)

= [ 27+(-17)] +[ 55+(-55)]

= 10 + 0 = 10

c) (-92) + (-251) + (-8) + 251

= [ (-92) + (-8)] + [ (-251)+251]

= (-100) + 0 = -100.

d) (-31) + (-95) +131 + (-5)

= [ (-31)+131] +[ (-95)+(-5)] = 100 + (-100) = 0

e) (187 - 23) - (20-180)

= 187 - 23 - 20 + 180 = (187-180) - (23-20) = 7 - 3 = 4

g) (-50+19+143) - (-79+25+48)

= -50+19+143 + 79 - 25 - 48

= [ -50-25] + (19 + 79) + 143 - 48

= -75 + 98 + 143 - 48 = 143 - 75 + ( 98 -48)

= 68 + 50 = 118

\(=\left(-50+19+143\right)-\left(-79+25+48\right)\)

\(=-50+19+143+79-25-48\)

\(=118\)

\(\left(-25\right)\left(75-45\right)-75\left(45-25\right)\)

\(\left(-25\right).30-75.20\)

\(=-2250\)

\(\left(-37-17\right).\left(-9\right)+35\left(-9-11\right)\)

\(-54.\left(-9\right)+35.\left(-20\right)\)

\(-763\)

Đánh mỏi tay quá

(-50+19+143)-(-79+25+48)

= 112 - -6

= 118

(-25)(75-45)-75(45-25)

=(-25) 30 - 75 20

= -750 - 1500

= -2250

(-37-17)(-9)+35(-9-11)

= 54 (-9)+ 35-20

= 486 + -700

= -214

(187-23)-(20-180)

= 164 - -160

= 324

512(2-128)-128(-512)

=512 (-126)-128(-512)

= 64512 - (-65536)

= 1024

17(-25)+25 21

= -425 + 525

= 100.

1/\(\left(-12\right)\cdot46-12\cdot54=\left(-12\right)\cdot46+\left(-12\right)\cdot54\)

\(=\left(-12\right)\cdot\left(46+54\right)=\left(-12\right)\cdot100=-1200\)

2/\(3784+23-3785-15=3785+22-3785-15\)

\(=22-15=7\)

3/\(\left(-8\right)\cdot25\cdot\left(-2\right)\cdot4\cdot\left(-5\right)\cdot125\)

\(=\left[\left(-8\right)\cdot125\right]\cdot\left[25\cdot4\right]\cdot\left[\left(-5\right)\cdot\left(-2\right)\right]\)

\(=\left(-1000\right)\cdot100\cdot10=-1000000\)

4/\(19\cdot25+9\cdot95+19\cdot30=19\cdot\left(25+30\right)+9\cdot95\)

\(=19\cdot55+9\cdot95=95\cdot11+9\cdot95=95\cdot\left(11+9\right)=20\cdot95=1900\)

5/\(\left(-50+19+143\right)-\left(-79+25+48\right)\)

\(=\left(-50\right)+19+143+79-25-48\)

\(=118\)

6/\(\left(-25\right)\cdot\left(75-45\right)-75\cdot\left(45-25\right)\)

\(=\left(-25\right)\cdot30+\left(-25\right)\cdot3\cdot20\)

\(=\left(-25\right)\cdot\left(30+60\right)=\left(-25\right)\cdot90=-2250\)

7/\(\left(-37-17\right)\cdot\left(-9\right)+35\left(-9-11\right)\)

\(=\left(-54\right)\cdot\left(-9\right)+35\cdot\left(-20\right)\)

\(=486+\left(-700\right)=-214\)

8/\(\left(187-23\right)-\left(20-180\right)\)

\(=187-23-20+180=324\)

9/\(512\cdot2-128\cdot\left(-512\right)\)

\(=512\cdot2+128\cdot512=512\cdot\left(2+128\right)\)

\(=512\cdot130=66560\)

10/\(17\cdot\left(-25\right)+25\cdot21\)

\(=17\cdot\left(-25\right)-\left(-25\right)\cdot21=\left(-25\right)\cdot\left(17-21\right)\)

\(=\left(-25\right)\cdot\left(-4\right)=100\)

Chúc bạn học tốt.

1) (-12).46-12.54

=12.(-46)-12.54

=12.(-46-54)

=12.(-100)=(-1200)

10) 17.(-25)+25.21

= (-17).25+25.21

=25.(-17+21)

=25.4=100

( Mik đọc lướt qua thì thấy hai bài này dễ nên làm, chứ mấy bài kia chưa suy nghĩ gì, bạn tự làm nốt nhé!)

2: \(=\left(3784-3785\right)+\left(23-15\right)=\left(-1\right)+8=7\)

3: \(=-8\cdot25\cdot2\cdot4\cdot5\cdot125\)

\(=-8\cdot125\cdot25\cdot4\cdot2\cdot5=-1000\cdot100\cdot10=-1000000\)

4: \(=19\left(25+9\cdot5+30\right)=19\cdot100=1900\)

5: \(=-50+19+143+79-25-48\)

\(=\left(-50-25+79\right)+143+19-48\)

=54+143-29

=143+25=168

6: \(=-25\cdot75+25\cdot45-75\cdot45+75\cdot25\)

\(=45\left(25-75\right)=45\cdot\left(-50\right)=-2250\)

7: \(=-54\cdot\left(-9\right)+35\cdot\left(-20\right)\)

\(=486-700=-214\)

8: \(=187-23-20+180=164+160=324\)

9: \(=512\left(2-128+128\right)=512\cdot2=1024\)