The volume of a rectangular prism is calculated using the formula:
\[ V_{\text{prism}} = \text{Base Area} \times \text{Height} \]
For a rectangular pyramid, the volume is given by the formula:
\[ V_{\text{pyramid}} = \frac{1}{3} \times \text{Base Area} \times \text{Height} \]
Since the base and height of the pyramid are congruent to those of the prism, we have:
\[ V_{\text{pyramid}} = \frac{1}{3} \times V_{\text{prism}} \]
Given that the volume of the rectangular prism is \(600 \text{ in}^3\):
\[ V_{\text{pyramid}} = \frac{1}{3} \times 600 \text{ in}^3 = 200 \text{ in}^3 \]
Therefore, the volume of the rectangular pyramid is 200 in.³.