tính hợp lí
a)29.(85-47)+85.(47-29)
b)47.(23+50)-23.(47+50)
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 hợp lí:
a. -29.(85-47)-85.(47-29)
b. 37.(29-23)-29.(37-23)
c. 5.2004-1002.(-10)+40.501
tính hợp lý
c1, -56+8(11+7)
c2, 47(23+50)-23(47+50)
c3, 85(47-29)+29(85-47)
c4, (-16)(-25)(-12)
c5, -19(16-25)+19(25-4)
c6, 11(16+24)+24(11-16)
c7, 29(85-47)-23(15-29)
c8, 15(23-29)+23(15-29)
c9, 13(55-29)-55(13-29)
c10, 37(27+25)+72(-25)
c11, (-216).68+32(-312)
c12, 44(-50)-50.56
c13, -69(-4).2-3(-7)(-2)
c14, 25.11.(-15)-50.15(-5)
c15, 47.69+31.(-47)
Tính hợp lí ( nếu được )
47 . ( 23 + 50 ) - 23 . ( 47 + 50 )
85 . ( 35 - 47 ) - 35 . ( 85 - 27 )
\(47\left(23+50\right)-23\left(47+50\right)=47.23+47.50-23.47-23.50=50\left(47-23\right)=1200\)
\(85\left(35-47\right)-35\left(85-27\right)=85.35-85.47-85.35+35.27=35.27-85.47=-3050\)
B1/ Tính nhanh :
a/ -29.(85-47)-85.(47-29)
b/ -15 . (23-29)+23.(15-29)
c/ 13. (55-29)+23.(15-29)
giải giúp mik nha
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
a/[25-(-75)]+32-(32+55)
=[25+75]+32-(32+55)
=25+75+32-32-55
=[25+75]+[32-32]-55
=100+0-55
=100-55
=45
7) -29.(85-47)-85.(47-29)
8) -15.(23-29)+23-(15-29)
9) -13.(55-29)+23.(15-29)
13)-10.(2+4)-5.(4-3)
-29.(85-47)-85.(47-29)
=-29.38-85.18
=-1102-1503
=-2605
-15.(23-29)+23-(15-29)
=-15.(-6)+23-(-14)
=90+23+14
=113+14
=127
-13.(55-29)+23.(15-29)
=-13.26+23.(-14)
=-338+(-322)
=-660
-10.(2+4)-5.(4-3)
=-10.6-5.1
=-60-5
=-65
bài 1 : Tính
a) -56+8.(11+7)
b) 47.(23+50)- 23 .(47+50)
c) 85.( 47-29)+29.(85-47)
d) -19.(16-25)+19.(-25-4)
e) 13.(55-29)-55.(13-29)
f) 44.(-50)-50.56
g) -47.69-31.47
bài 2 : tìm x :
a) 10.(x-7)-8.(x-4)=x
b) 9.(x+4)-4.(2x+15)=3
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