The appropriate way to check that the volume of the right rectangular prism is correct is to use the formula method to see if the volume is the same.
To do this, you can use the formula for the volume of a right rectangular prism, which is:
\[ \text{Volume} = \text{length} \times \text{width} \times \text{height} \]
By substituting the edge lengths into this formula, you can verify if the calculated volume matches the reported volume of 78 cubic units.