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

1089.24350205

\(A=\frac{595959}{454545}-\frac{14141414}{15151515}\)

\(A=\frac{595959:10101}{454545:10101}-\frac{14141414:1010101}{15151515:1010101}\)

\(A=\frac{59}{45}-\frac{14}{15}\)

\(A=\frac{59}{45}-\frac{42}{45}=\frac{17}{45}\)

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

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

\(B=\frac{200+1800}{800-300}=\frac{2000}{500}=4\)

Giải theo cách lớp 5

\(A=\frac{595959}{454545}-\frac{14141414}{15151515}\\ A=\frac{595959:10101}{454545:10101}-\frac{14141414:1010101}{15151515:1010101}\\ A=\frac{59}{45}-\frac{14}{15}=\frac{17}{45}\)

\(B=\frac{65+891+135+909}{731-47+69-253}=\frac{\left(65+135\right)+\left(891+909\right)}{\left(731+69\right)-\left(47-253\right)}=\frac{200+1800}{731+69-47+253}=\frac{200+1800}{500}=\frac{2000}{500}=4\)

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

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

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

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

Ta có:

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

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

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

\(\Leftrightarrow C=\frac{2000}{500}=4\)

a) 27.121-87.27+73.34

=27.(121-87)+73.34

=27.34+73.34

=34(27+73)

=34.100

=3400

b) 48.19+134.52+48.115

=48.19+48.115+134.52

=48(19+115)+134.52

=48.134+134.52

=134(48+52)

=134.100

=13400

c) 65+891+135+909/731-47+69-253

VT:(65+135)+(891+909)

=200+1800

=2000

VP:(731+69)-(253+47)

=800-300

=500

2000/500=4

d)18.123+9.4576.2+3.5310.6/1+4+7+..+55+58-410

VT:18.123+18.4567+18.5310

=18(123+4567+5310)

=18.10009

=18(10000+9)

=180000

VP:Tổng : 1+4+7+...+55+58 

Có số số hạng là : 

(58-1):3+1=20( số )

Tổng bằng : (58+1).20:2=590

590-410=180

180000:180=1000

Mình chữa câu d tí 9.4576.2 là sai ;;; 9.4567.2 mới đúng 

sao ko ai giúp em vậygianroi