17/35 và 171717/353535                                                                    

Rút gọn: 171717/353535=171717:10101/353535:10101=17/35.          

Mà 17/35=17/35                                                                                  

171717/353535=17/35 

1/ Ta có : \(\frac{212121}{353535}=\frac{3.7.10101}{5.7.10101}=\frac{3}{5}=\frac{42}{70}\)

\(\frac{131313}{141414}=\frac{13.10101}{14.10101}=\frac{13}{14}=\frac{65}{70}\)

Vì 42 < 65 =>  \(\frac{42}{70}<\frac{65}{70}\)  =>  \(\frac{212121}{353535}<\frac{131313}{141414}\)

1)Ta có : 212121/353535 = 212121:10101/353535:10101 = 21/35 = 3/5

131313/141414 = 131313:10101/141414:10101 = 13/14

Ta có : 3/5 = 42/70 ; 13/14 = 65/70

Vì 42<65 => 42/70<65/70 => 212121/353535<131313/141414

2)Ta có : 2012/2013<1 

2013/2014<1

2014/2015<1

=> 2012/2013+ 2013/2014+ 2015/2012<1+1+1=3

Vậy 2012/2013+ 2013/2014+ 2015/2012<3

Ai chơi truy kích cấp cao thì kết bạn nha !!!!!!!!

212121/353535=21/35=3/5

131313/141414=13/14. 

b, 2012/2013<1; 2013/2014<1; 2014/2015<1 nên  2012/2013+2013/2014+ 2014/2015<3

353535/676767

=35.10101/67.10101

=35/67

Ta có: 35/67>35/69>34/69

=> 353535/676767>34/69

27272727/53535353

=27.1010101/53.1010101

=27/53

Ta có: 27/53<1<1.2

=> 27272727/53535353<1 .2

chúc bạn học tốt nha

ủng hộ mk bằng cách tk nha

\(\frac{252525}{373737}=\frac{252525:10101}{373737:10101}=\frac{25}{37}\)

\(\frac{272727}{353535}=\frac{272727:10101}{353535:10101}=\frac{27}{35}>\frac{27}{37}>\frac{25}{37}\)

vậy \(\frac{252525}{373737}

\(\frac{252525}{373737}=\frac{25.10101}{37.10101}=\frac{25}{37}=\frac{875}{1295}\)

\(\frac{272727}{353535}=\frac{27.10101}{35.10101}=\frac{27}{35}=\frac{999}{1295}\)

Vì \(\frac{875}{1295}

\(\frac{252525}{373737}=\frac{252525:10101}{373737:10101}=\frac{25}{37};\frac{272727}{353535}=\frac{272727:10101}{353535:10101}=\frac{27}{35}\)

=>25/37<27/35

thì bn quy đòng mẫu số hai phân số ra

rùi xem p/s nào có tử số lớn hơn thì lớn hơn 

\(\frac{181818}{242424}=\frac{181818:10101}{242424:10101}=\frac{18}{24}=\frac{18:6}{24:6}=\frac{3}{4}\)

\(\frac{181818}{242424}=\frac{181818\div10101}{242424\div10101}=\frac{18}{24}\)

\(\frac{252525}{353535}=\frac{252525\div10101}{353535\div10101}=\frac{25}{35}\)

Ta có : \(\frac{18}{24}=\frac{18\times35}{24\times35}=\frac{630}{840};\frac{25}{35}=\frac{25\times24}{35\times24}=\frac{600}{840}\)

Vì \(\frac{630}{840}>\frac{600}{840}\)nên \(\frac{181818}{242424}>\frac{252525}{353535}\)