Conjoints work the same way only backwards. If you've got a feasibility relation \\(\Phi \colon X \nrightarrow Y \\) and you want it to be the conjoint of some function \\(G \colon Y \to X\\), you need

\\(\Phi(x,y) = \text{true} \\) iff \\(x \le G(y) \\).

But in Puzzle 207, which is about buying loaves of bread, the obvious first guess would be a function \\(G\\) such that

\\(y\\) dollars can buy \\(G(y) \\) loaves of bread.