Brand a: 240 mg sodium for 1/3 pickle or brand b: 325 mg sodium for 1/2 pickle.

Not sure what you're asking.. if you're trying to decide which one's the better/ more efficient way to go with,you would take 240 * 3 = 720 for A and for B, 325 * 2 = 650. so Brand A would be less efficient or it uses more sodium per pickle.

Brand A: 720mg sodium per pickle
Brand B: 650mg sodium per pickle