Answer:
David took 16 oranges.
Explanation:
We are given the following in the question:
Total number of oranges = 48
Oranges rotten =

Number of oranges rotten =

There were 16 rotten oranges.
Number of good oranges left =

These are equally divided among Ben and David.
Number of oranges each Ben and David get =

Thus, David took 16 oranges.