Bài 1 : Tính
1) (-12).13+13.(-22) 2)(-79).(-88)+(-21).(-88)
3)11.107+11.18-25.11 4) 5.4-15.5+7
5) 60.(45-15)-45.(60-15) 6)85.(17-35)-18.(40-55)
7) 2155-(174+2155)+(-68+174) 8)-25.72+25.21-49.25
9)8154-(674+8154)+(-98+674) 10) 44.(-36)+22.(-28)
@isa
Bài 1 : Tính
`1) (-12).13+13.(-22)`
`= (- 156) + (- 286)`
`= (- 442)`
`2)(-79).(-88)+(-21).(-88)`
`= 6952 + 1848`
`= 8800`
`3)11.107+11.18-25.11`
`= 1177 + 198 – 275`
`= 1375 – 275`
`= 1100`
`4) 5.4-15.5+7`
`= 20 – 75 + 7`
`= – 55 + 7`
`= – 48`
`5) 60.(45-15)-45.(60-15)`
`= 1800 – 2025`
`= – 225`
`6)85.(17-35)-18.(40-55)`
`= – 1530 + 270`
`= – 1260`
`7) 2155-(174+2155)+(-68+174)`
`= – 174 + 106`
`= – 68`
`8)-25.72+25.21-49.25`
`= – 1800 +525 – 1225`
`= – 1275 – 1225`
`= – 2500`
`9)8154-(674+8154)+(-98+674)`
`= – 674 + 576`
`= – 98`
`10) 44.(-36)+22.(-28)`
`= – 1584 – 616 `
`= – 2200`
Chúc bn hc tốt !!
Đáp án:
1) (-12).13+13.(-22)
= (- 156) + (- 286)
= (- 442)
2)(-79).(-88)+(-21).(-88)
= 6952 + 1848
= 8800
3)11.107+11.18-25.11
= 1177 + 198 – 275
= 1375 – 275
= 1100
4) 5.4-15.5+7
= 20 – 75 + 7
= – 55 + 7
= – 48
5) 60.(45-15)-45.(60-15)
= 1800 – 2025
= – 225
6)85.(17-35)-18.(40-55)
= – 1530 + 270
= – 1260
7) 2155-(174+2155)+(-68+174)
= – 174 + 106
= – 68
8)-25.72+25.21-49.25
= – 1800 +525 – 1225
= – 1275 – 1225
= – 2500
9)8154-(674+8154)+(-98+674)
= – 674 + 576
= – 98
10) 44.(-36)+22.(-28)
= – 1584 – 616
= – 2200
Chúc bn hc tốt !!
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