Ta có :
`{-3}/4 = {-6}/8 > {-7}/8`
`{-2}/3 = {-8}/{12} `
`{-3}/4 = {-9}/12`
`=> {-2}/3 > {-3}/4 > \hat{-7}/8`
`{-7}/8 = -0,875`
`{-18}/19 = -0,947 ...`
`{-27}/28 = 0,964 ...`
`=> {-7}/8 > \hat{-18}/19 > {-27}/28`
`=> {-2}/3 > {-3}/4 > {-7}/8 > {-18}/19 > {-27}/28`
Sắp xếp theo thứ tự giảm dần :
`{-2}/3 ; {-3}/4 ; {-7}/8 ; {-18}/19 ; {-27}/28`