Bài 1 : Tính tổng sau một cách hợp lí :
a ) 34 + 35 + 36 + 37 – 24 – 25 – 26 – 27
b ) 55 – 737 – 463 + 45
c ) -85 + 10 -(-85) – 50
d ) 71 -(-30) – 37 – 81 + 37
e ) -56 + 26 + 14 + 156
f ) 1632 – 37 -(-157) – 163 – 1532
g ) 20 – |-46| – 25 – (-46)
h ) 35 – (-78) – 49 – 78 -|-35|
Nhanh nhé mik đang cần gấp
Bài 1:
a)34 + 35 + 36 + 37 – 24 – 25 – 26 – 27
=(34-24)+(35-25)+(36-26)+(37-27)
= 10 + 10 + 10 + 10 = 40
b)55 – 737 – 463 + 45
= 55 – (737 + 463) + 45
= 55 -1200 + 45
= 55 + 45 – 1200 = 100 -1200 = -1100
c)-85 + 10 -(-85) – 50
= -85 – (-85) + (10-50)
= -85 + 85 + (-40)
= 0 – 40 = -40
d) 71 -(-30) – 37 – 81 + 37
= 71 + 30 +(-37 + 37) – 81
= 101 – 81 = 20
e) -56 + 26 + 14 + 156
=(-56+156) + (26+14)
= 100 + 40
= 140
f) 1632 – 37 -(-157) – 163 – 1532
= 1632 – 37 + 157 – 163 – 1532
= 1632 -(37 + 163) -1532 + 157
= 1632 – 200 – 1532 + 157
= -100 + 157 = 57
g ) 20 – |-46| – 25 – (-46)
= 20 – 46 – 25 + 46
= (20 – 25) + (-46+46)
= -5 + 0 = -5
h)35 – (-78) – 49 – 78 -|-35|
= 35 + 78 – 49 – 78 – 35
= (35-35)+(78-78) – 49
= 0 + 0 – 49 = -49
Đáp án + Giải thích các bước giải:
Ta có :
`a,34+35+36+37-24-25-26-27`
`=(34-24)+(35-25)+(36-26)+(37-27)`
`=10+10+10+10`
`=40`
`b,55-737-463+45`
`=(55+45)-(737+463)`
`=100-1200`
`=-1100`
`c,-85+10-(-85)-50`
`=-85+10+85-50`
`=(85-85)-(50-10)`
`=0-40`
`=-40`
`d,71-(-30)-37-81+37`
`=71+30-37-81+37`
`=(71+30-81)+(37-37)`
`=20+0`
`=20`
`e,-56+26+14+156`
`=(156-56)+(26+14)`
`=100+40`
`=140`
`f,1632-37-(-157)-163-1532`
`=1632-37+157-163-1532`
`=(1632-1532)-(163+37)+157`
`=100-200+157`
`=-100+157`
`=57`
`g,20-|-46|-25-(-46)`
`=20-46-25+46`
`=(20-25)+(46-46)`
`=-5+0`
`=-5`
`h,35-(-78)-49-78-|-35|`
`=35+78-49-78-35`
`=(35-35)+(78-78)-49`
`=0+0-49`
`=-49`