a , 1000 - 121 - 79
b , ( - 400 ) - (13 - 47 )
c , ( - 215 ) + 63 + 37
d , ( - 147 ) - ( 13 - 47 )
e , 1945 + {( - 1945 ) - 17)}
f , ( - 2020 ) - {( - 2020 ) - 11 }
g , ( - 44 ) + {( -14 ) -30}
h , ( 45 - 3756 ) + 3756
em đang cần gấp ạ
tinh nhanh
a. 47.[23+50]-23.[47+50]
b,29.[85-47]+85.[47-29]
c,37.90-37.[-10]
d,15.12-3.5.10
e,29.[19-13]-19.[29-13]
f,33.[17-5]-17.[33-5]
g,54-6.[17+9]
h,1000+[-570]+2341+[-430]
nhiều quá mk phụ bạn chút thôi
a)47*(23+50)-23*(47+50)=47*23+47*50-23*47+23*50=(47*23-23*47)+(47*50+23*50)=(47+23)*50=70*50=3500
b)29*(85-47)+85*(47-29)=29*85-29*47+85*47-85*29=(29*85-85*29)+(85*47-29*47)=(85-29)*47=56*47=2632
c)37*90-37*(-10)=37*[90-(-10)]=37*100=3700
a. 47.[23+50]-23.[47+50]
=47.73-23.97
=3431-2231
=1200
b,29.[85-47]+85.[47-29]
=29.38+85.18
=1102+1520
=-428
c,37.90-37.[-10]
=37.(90-(-10))
=37.100
=3700
d,15.12-3.5.10
=15.12-15.10
=15.(12-10)
=15.2
=30
e,29.[19-13]-19.[29-13]
=29.6-19.16
=174-304
=-130
f,33.[17-5]-17.[33-5]
=33.12-17.32
=396-544
=-148
g,54-6.[17+9]
=54-6.26
=54-156
=-102
h,1000+[-570]+2341+[-430]
=430+2341+(-430)
=(-430+430)+2341
=0+2341
=2341
tính nhanh
a/[25-(-75)]+32-(32+55)
b/25.17.(-4).125.(-8)
c/(-14).9-13.(-9)
d/37.90-37.(-10)
e/29.(100-47)+85.(47-29)
f/47.(23+50)-23.(47+50)
g/45-5.(17+9)-17.(-15)
h/(-8).(-25)+52.23
tính nhanh
a/[25-(-75)]+32-(32+55)
b/25.17.(-4).125.(-8)
c/(-14).9-13.(-9)
d/37.90-37.(-10)
e/29.(100-47)+85.(47-29)
f/47.(23+50)-23.(47+50)
g/45-5.(17+9)-17.(-15)
h/(-8).(-25)+52.23
Bài 6 : Tính hợp lí
1 . (-232)+55+(-63)+45
2 . (-205)+21+205+75
3 . 131+269+(-59)+(-131)
4 . (-196)+189+20+(-604)+(-199)
5 . (-170)+43+(-143)
6 . (-43)+(-17)+(-25)
7 . (-249)+121+I-29I+(-121)
8 . (-47)+(-139)+47+169
9 . (-13)+(-7)+(-75)
10 . (-9)+37+(-11)
11 . 12+(-23)+53
12 . (-3)+(-25)+23
13 . (-26)+10+(-14)
14 . (-13)+6+(-37)+14
15 . (-11)+(-9)+5+25
16 . (-12)+(-18)+8
17 . 315+[135+(-315)+(-35)]
18 . 815+[95+(-915)+(-45)]
19 . 5+(-7)+9+(-11)+13+(-15)
20 . (-10)+12+(-14)+16+(-18)+20
Tính hợp lý (nếu có thể)
a) (-17) + 21 + 79 +17
b) 40 + 22 + ( - 16) + ( - 44)
c) (-12) + (- 47) + (-28) + 47
d) ( -5) + (-3) + 35 + (-17)
e) 21.23-3.7.(-17)
f) 42.3-7.[(-34)+18]
g) 71.64+32.(-7)-13.32
h) 13. (23-17)-13.(23+17)
TRÌNH BÀY RÕ RÀNG HỘ MIK NHA !!
AI NHANH THÌ MIK TICK NHA
a, (-17) + 21 + 79 + 17
= (-17 + 17) + (21 + 79)
= 0 + 100
= 100
b, 40 + 22 + (-16) + (-44)
= 40 + {(-16) + (-44} + 22
= 40 - 60 + 22
= - 20 + 22
= 2
c, (-12) + (-47) + (-28) + 47
= - (12 + 28) + (-47 + 47)
= - 40 + 0
= - 40
d, (- 5) + (-3) + 35 + (-17)
= (-5 + 35) - (3 + 17)
= 30 - 20
= 10
e, 21.23 - 3.7.(-17)
= 21.23 + 21.17
= 21.(23 + 17)
= 21. 40
= 840
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+21+22+23+24+25+26+27+28+29+30+31+32+33+34+35+36+37+38+39+40+41+42+43+44+45+46+47+48+49+50+51+52+53+54+56+57+58+59+60+61+62+63+64+65+66+67+68+69+70=?
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+21+22+23+24+25+26+27+28+29+30+31+32+33+34+35+36+37+38+39+40+41+42+43+44+45+46+47+48+49+50=?
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+21+22+23+24+25+26+27+28+29+30+31+32+33+34+35+36+37+38+39+40+41+42+43+44+45+46+47+48+49+50=1275
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+21+22+23+24+25+26+27+28+29+30+31+32+33+34+35+36+37+38+39+40+41+42+43+44+45+46+47+48+49+50.
Có ai rảnh đâu mà đi ngồi cộng ngần đấy số ra.