Text: Sure, I might be able to sell them to a used software store, but I wouldn't be able to get more than $5 or so because those stores must mark them up so substantially to cover their own costs.
Entailment: I could probably sell them to a store but I wouldn't get much money because the software store has to make a profit too.
Contradiction: If I sell them to the software store, I'll be able to get $10 a piece.