Yes, because if you change 1 1/3 into an improper fraction (4/3) and then multiply by causing 4 (as in the 4 bags) to become its reciprocal form (1/4), you can solve the problem and find out that each bag can hold 1/3 of the trail mix.
Another way to solve this is by drawing a rectangle, dividing it into 4ths and writing that each divided section represents 1/3. 4 1/3s = 1 1/3.