`a)`
`23/27 = (23 xx 41)/(27 xx 41) = 943/1107`
`27/41 = (27 xx 27)/(41 xx 27) = 729/1107`
Vì `943/1107 > 729/1107` nên `23/27 > 27/41`
`b)`
`23/47= (23 xx 45)/(47 xx 45) = 1035/2115`
`24/45 = (24 xx 47)/(45 xx 47) = 1128/2115`
Vì `1035/2115 < 1128/2115` nên `23/47 < 24/45`
`c)`
`43/47 = 1 - 4/47`
`31/35 = 1 - 4/35`
Ta thấy : `4/47 < 4/35`
Do đó : `1 - 4/47 > 1 -4/35`
Hay : `43/47 > 31/35`
`d)`
`16/27 = (16 xx 29)/(27 xx 29) = 464/783`
`15/29 = (15 xx 27)/(29 xx27) = 405/783`
Vì `464/783 > 405/783` nên `16/27 > 15/29`
`e)`
`23/28 = (23 xx 27)/(28 xx27) = 621/756`
`24/27 = (24 xx 28)/(27 xx 28) = 672/756`
Vì `621/756 < 672/756` nên `23/28 < 24/27`
`f)`
`13/15 = 130/150 = 1 - 20/150`
`133/153 = 1 - 20/153`
Ta thấy : `20/150 > 20/153`
Do đó : `1 - 20/150 < 1 - 20/153`
Hay : `13/15 < 133/153`
`g)`
`13/15 = 1443/1665 = 1 - 222/1665`
`1333/1555 = 1 - 222/1555`
Ta thấy : `200/1665 < 200/1555`
Do đó : `1 - 200/1665 > 1- 200/1555`
Hay : `13/15 > 1333/1555`
