To determine how many ounces your friend ate, you need to calculate \( \frac{1}{4} \) of the total weight of the popcorn, which is \( 13 \frac{1}{3} \) ounces.
First, let's convert \( 13 \frac{1}{3} \) ounces to an improper fraction:
\[
13 \frac{1}{3} = 13 + \frac{1}{3} = \frac{39}{3} + \frac{1}{3} = \frac{40}{3} \text{ ounces}
\]
Now, calculate \( \frac{1}{4} \) of \( \frac{40}{3} \):
\[
\frac{1}{4} \times \frac{40}{3} = \frac{40}{12} = \frac{10}{3} \text{ ounces}
\]
Next, convert \( \frac{10}{3} \) back to a mixed number:
\[
\frac{10}{3} = 3 \frac{1}{3} \text{ ounces}
\]
Since \( 3 \frac{1}{3} \) isn't listed among your options, let's reevaluate our initial choices.
However, deducing from the given options, the closest and possibly incorrect portrayal of the calculation appears to be 3 \( \frac{1}{3} \) ounces, although it was not included precisely as such in your responses.
Please ensure that the options match properly or provide other possible responses for a more accurate re-evaluation!