Answer:
The volume of the rectangular prism is <u>19.25 inches³</u>.
Step-by-step explanation:
Given:
It takes 154 cubes with side lengths of 1/2 inch to fill a rectangular prism.
Now, to find the rectangular prism's volume.
We first find the volume of a cube to fill in the rectangular prism.
The side length of the cube = 
Now, to get the volume of cube we put formula:

<em>Thus, the volume of a cube is </em>
<em />
<em>Number of cubes = 154.</em>
<u><em>According to question, it takes 154 cubes to fill the rectangular prism.</em></u>
<u><em>So, to get the volume of prism we need to find the volume of 154 cubes.</em></u>
Now, to get the volume of 154 such cubes we multiply the volume of a cube by number of cubes:

Therefore, the volume of the rectangular prism is 19.25 inches³.