cs ai giải hộ mik ko ạ, mik gấp lắm

a: =300-224=76

b: =-100+329=229

a) 0.            b) 5 8          

c) 0 .       d) 0 .

Ai nhanh mk tick cho

tui 

Bài 1. Tính bằng cách thuận tiện nhất:

a) 461 x 42 + 461 x 58=461x(42+58)=461x100=46100                      

b) 396 x 37 – 396 x 17=396x(37-17)=396x20=7920

c) 47 x 298 + 53 x 298=298x(47+53)=298x100=29800                   

d) 253 x 284 + 253 x 482 +253 x 234=253x(284+482+234)=253x1000=253000 

e) 426 x 617 + 617 x 574=617x(426+574)=617x1000=617000                    g) 672 x 100 – 672 x 50 + 336 x 500=672 x 100 – 672 x 50 + 336 x 2 x 250=72 x 100 – 672 x 50 + 672x250=672x(100-50+250)=672x300=201600

Bài 2. Viết số thích hợp vào chỗ chấm :

a) 10kg =1 yến                         30kg = 3 yến                             10 yến = 1 tạ

400 kg = 4 tạ                             10 tạ = 1tấn                              4000kg = 4 tấn

b) 100cm²= 1dm²                      2500cm² = 25 dm²                      1 m² = 100 dm²

15 m² = 1500 dm²                           300 dm² = 3 m²                         7500 dm² = 75 m²

Sao mình thấy cái đề này quen quen

253 x 75 - 161 x 37 + 253 x 25 - 161 x 63

= 253 x (75 + 25) - 161 x (37 + 63)

=253 x 100 - 161 x 100

=23500 - 16100

=37400

100 x 47 - 12 x 3,5 - 5,8 : 0,1

=4700 - 42 - 58

=4700 - (42 + 58)

=4700 - 100

=4600

Đáp số là 7850 và 4600. 

Tk nha.

65+891+135+909 phần 731-47+69-253 = 2000 phần 500 =4

Đặt a=2013

\(\Rightarrow M=\sqrt{1+a^2+\frac{a^2}{\left(a+1\right)^2}}+\frac{a}{a+1}\)

\(\Rightarrow M=\sqrt{\frac{\left(a+1\right)^2+a^2\left(a+1\right)^2+a^2}{\left(a+1\right)^2}}+\frac{a}{a+1}\)

\(\Rightarrow M=\sqrt{\frac{a^2+2a+1+a^4+2a^3+a^2+a^2}{\left(a+1\right)^2}}+\frac{a}{a+1}\)

\(\Rightarrow M=\sqrt{\frac{\left(a^4+2a^3+a^2\right)+2\left(a^2+a\right)+1}{\left(a+1\right)^2}}+\frac{a}{a+1}\)

\(\Rightarrow M=\sqrt{\left(\frac{a^2+a+1}{a+1}\right)^2}+\frac{a}{a+1}\)

\(\Rightarrow M=\frac{a^2+a+1+a}{a+1}\)(Bỏ trị tuyệt đối vì a=2013)

\(\Rightarrow M=\frac{a^2+2a+1}{a+1}=\frac{\left(a+1\right)^2}{a+1}=a+1=1013+1=1014\)

\(A=\frac{65+891+135+909}{731-47+69-253}\)

\(A=\frac{65+135+891+909}{731+69-47-253}\)

\(A=\frac{\left(65+135\right)+\left(891+909\right)}{\left(731+69\right)-\left(47+253\right)}\)

\(A=\frac{200+1800}{800-300}\)

\(A=\frac{2000}{500}=4\)

A = \(\frac{65+891+135+909}{731-47+69-253}\)

A = \(\frac{\left(65+135\right)+\left(891+909\right)}{\left(731+69\right)-\left(47+253\right)}\)

A = \(\frac{200+1800}{800-300}\)

A = \(\frac{2000}{500}\)

A = 4

\(A=\frac{65+891+135+909}{731-47+69-253}\)

\(A=\frac{5\times13+9\times9\times11+5\times27+9\times101}{17\times43-47+23\times3-11\times23}\)

\(A=\frac{5\times13+5\times27+9\times99+9\times101}{17\times43-47-11\times23+23\times3}\)

\(A=\frac{5\times\left(13+27\right)+9\times\left(99+101\right)}{17\times43-47-23\times\left(11-3\right)}\)

\(A=\frac{5\times40+9\times200}{17\times43-47-23\times8}\)

\(A=\frac{2000}{500}\)

\(A=4\)

no tính nhanh đc rùi! cho mk xin lỗi bn nhiều nha!!!!