Final answer:
The total space inside the fort is 2.4375 cubic meters.
Step-by-step explanation:
To find the total space inside the fort, we need to calculate the volume of each box and then add them together.
The volume of the first box is 0.75 m x 0.5 m x 0.5 m = 0.1875 m³.
The volume of the second box is 1.5 m x 1 m x 1.5 m = 2.25 m³.
Adding the volumes of the two boxes, we get a total volume of 0.1875 m³ + 2.25 m³ = 2.4375 m³.
Therefore, the total space inside the fort is 2.4375 cubic meters.