A rectangular tiling field is 2550×3450 mm after perimeter gaps have already been deducted. Square tiles have side 300 mm; internal joints are 5 mm. For this exercise choose full interior tiles across an axis as floor((field+j)/(tile+j))−1, then use two equal cut borders. There are n+1 joints around n full interior tiles. Each edge or corner piece consumes its own tile; reuse of offcuts is excluded.
Calculate the full interior tiles across the width. Keep intermediate values unrounded; round the final answer to 4 decimal places if needed.
