` - 5/18 +7/24 = -20/72 + 21/72 = (-20+21)/72 = 1/72`
` -18/24 + -27/-72 = -18/24 + ((-27)/(-72)) = -18/24 + 27/72 = -54/72 +27/72 = (-54/72) + 27/72 =-3/8`
Ta có
` 1 + (-13/14) = 1/14`
` 1+ (-11/12) = 1/12`
Vì ` 1/12 > 1/14`
Nên ` 1 + (-11/12) > 1 + (-13/14) `
`\to 1 -11/12 > 1 -13/14`
` \to 11/12 < 13/14`
`\to -11/12 > -13/14`