`11/12 <1`

`17/8 >1`

`=>11/12 < 17/8`

``

`2018/2020 > (2018-1)/(2020-1)=2017/2019`

`->2018/2020 > 2017/2019`

``

`77/76=1+1/76`

`84/63=1+21/63`

`Vì  1/76 < 21/63`

`=>77/76 < 84/63`

``

`2013/2010 < (2013+5)/(2010+5)=2018/2015`

`=>2013/2010 < 2018/2015`

`

`-387/386 > -(387+205)/(386+205)=-592/591`

`=>-387/386 > -592/591`

``

`-1999/2000 > -(1999+1)/(2000+1)=-2000/2001`

`=>-1999/2000 > -2000/2001`