Question

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]

 

Answer 1

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

Answer 2

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