Answer:
64.
Step-by-step explanation:
We identify in the original equation what data we have and what we lack:

The problem statement gives us Y / L, which is the real GDP per worker = 3200, so we would lack K / L, which is the physical capital per worker, precisely, the data requested by the exercise. Therefore:

To find K / L we make a simple clearance:


The physical capital equals 64.