Answer:
The number of fish in the tank are 9.
Explanation:
As given
The volume of a fish tank is 30 cubic feet.
If the density is 0.3 fish over feet cubed .

Where N is the number of fish , V is the volume of a fish and d is the density of a fish .
Put values in the above

N= 0.3 × 30
N = 9
Therefore the number of fish in the tank are 9.