Final answer:
To find the volume of a pyramid with a square base, use the formula V = 1/3 × base area × height. In this case, the volume is approximately 43m³.
Step-by-step explanation:
To find the volume of a pyramid with a square base, we use the formula V = 1/3 × base area × height. In this case, the base is a square, so we need to find the area of the square base first. The perimeter of the square base is given as 12.8m, so the length of each side of the square is 12.8m / 4 = 3.2m. The area of the square base is 3.2m × 3.2m = 10.24m². Now, we can calculate the volume using the formula V = 1/3 × 10.24m² × 12.5m. Plugging in the values, we get V = 1/3 × 10.24m² × 12.5m = 43.008m³. Rounding to the nearest tenth, the volume of the pyramid is approximately 43m³.