The volume of a rectangular prism is calculated by multiplying the length, width, and height.
Volume = length x width x height
Volume = (2 1/4 ft) x (3 1/8 ft) x (2 1/2 ft)
Volume = (9/4 ft) x (25/8 ft) x (5/2 ft)
Volume = (9 x 25 x 5)/(4 x 8 x 2) ft^3
Volume = 1125/64 ft^3
To simplify this fraction, we need to divide both the numerator and denominator by the greatest common factor, which is 1 in this case.
Volume = 1125/64 ft^3 = 1125 ft^3 / 64
Volume = 17 37/64 ft^3
Therefore, the volume of the rectangular prism is 17 37/64 cubic feet.