Explanation:
remember, a/a = 1, and it represents always a "whole" in fraction calculations.
in our case here : 4/4.
if I understand correctly, he packs 1/3 of 6 3/4 pounds into pound bags (which I assume are bags that hold 1 pound each).
6 3/4 = (6×4)/4 + 3/4 = 24/4 + 3/4 = 27/4 pounds.
1/3 of x means multiplying x by 1/3.
this is the same as dividing x by 3.
so, in our case 1/3 of the candy to be packed is
27/4 × 1/3 = 27/(4×3) = 9/4 = 8/4 + 1/4 = (2×4)/4 + 1/4.
that means he can fill 2 whole pound bags and has 1/4 pound left.