I think it would be logical if the given information are the dimensions of the water container which should be 200 cm × 633 cm. Supposing the water container is in the shape of the rectangle, the area would just be the product of the dimensions. Convert cm first to m to be consistent with units. (100 cm = 1 m)
Area = (200 cm * 1 m/100 cm)(633 cm * 1m/100 cm)
Area = 12.66 m²
