My notes really don't explain this clearly at all, so I have no idea what to do.
If I have the following MILP:

In which I've been told to solve it using:
(a) Rule 1 (choose the variable with the largest max$\{p_D(x) ,p_U(U) \}$ ;
(b) Rule 3 (choose the variable with the smallest min$\{p_D(x) ,p_U(U) \}$
For:
$p_D(x) =$ down penalty ; $p_U(U) = $ up penalty
They arrive at the following calculation for up and down penalties, from the LP-relaxation:

Can someone please explain to me how they got to this calculation for penalties, because I haven't been told how to do it in my notes, thanks.