Question

1,(-12).46-12.54

2,3784+23-3785-15

3,(-8).25.(-2).4.(-5).125

4,19.25+9.95+19.30

5,(-50+19+143)-(-79+25+48)

6,(-25).(75-45)-75(45-25)

7,(-37-17).(-9)+35.(-9-11)

8,(187-23)-(20-180)

9,512.(2-128)-128.(-512)

10,17.(-25)+25.21

Answer 1

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!)

Answer 2

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