The density of a fish tank is 0.4 fish over feet cubed. there are 12 fish in the tank. what is the volume of the tank? will fan and medal

The answer is:  30 ft³ ;  or, write as:  30 cubic feet .

Explanation: 

Given:

Density = 0.4 fish(es) per cubic foot (or, feet);

or, "Density = 0.4 fish / ft³ ;

And, given: "12 fish in the tank." ;

And Density = (value; in this case, "number of fish" / unit volume);

We are given:  Density, "D" = 0.4 fish / 1 ft³

In our case, our volume is in "cubic ft." ; or, "ft³ ;

We want to find the actual volume of the tank (in "cubic feet"; or, " ft³ ");

 →  (1 ft³ / 0.4 fish) * 12 fish  = ?  ft³ ?

 →  On the "left-hand side" of the equation; the units of "fish" cancel out to "1"; and we are left with units of "ft³ " ; which is the units for which we wish to solve.

  → So, so have  (1 ft³ * 12) / (0.4) = 12 ft³ / 0.4 = 30 ft³ .

  → The answer is:  30 ft³ ;  or, write as:  30 cubic feet .