To calculate the volume of a square pyramid, you can use the formula:
\[ V = \frac{1}{3} \times \text{Base Area} \times \text{Height} \]
For a square base, the base area can be calculated as:
\[ \text{Base Area} = \text{side}^2 \]
Given that the side of the square base is 125 meters, the base area is:
\[ \text{Base Area} = 125 , \text{m} \times 125 , \text{m} = 15625 , \text{m}^2 \]
The height of the pyramid is given as 324 meters.
Now we can calculate the volume:
\[ V = \frac{1}{3} \times 15625 , \text{m}^2 \times 324 , \text{m} \]
Calculating that:
\[ V = \frac{1}{3} \times 15625 \times 324 = \frac{5062500}{3} = 1687500 , \text{m}^3 \]
Thus, the volume of the Eiffel Tower, if the sides were solid, would be 1,687,500 cubic meters.