Final answer:
The area of the largest square that can be fitted into the remaining space is 21 square inches.
Step-by-step explanation:
The area of the largest square that can be fitted into the remaining space can be found by subtracting the area of the smaller squares from the area of the original square.
Since each side of the original square is 5 inches long, the area of the original square is 5 inches x 5 inches = 25 square inches.
The four smaller squares have side lengths of 1 inch, so each one has an area of 1 inch x 1 inch = 1 square inch. The total area of the four smaller squares is 4 square inches.
Subtracting the area of the smaller squares from the area of the original square, we get 25 square inches - 4 square inches = 21 square inches.
Therefore, the area of the largest square that can be fitted into the remaining space is 21 square inches.