How many square meters 80gsm paper per tonne?

The number of square meters of 80gsm (grams per square meter) paper in a tonne can be calculated using the formula: area (m²) = weight (kg) / (gsm / 1000). Since 1 tonne equals 1000 kg, the calculation would be 1000 kg / (80 gsm / 1000) = 12,500 m². Therefore, there are approximately 12,500 square meters of 80gsm paper in one tonne.