ISRO Draughtsman-B Mechanical Question Paper - 2015 (Set -1) with Answer Key

The area of each of the A paper sizes are set by the A paper size definitions. A0 is defined as having an area of 1 square metre, however the A paper size standard also specifies that each size is rounded to the nearest millimetre.

Thus A0 is 841 mm x 1189 mm giving an area of 0.999949 square metres. Approximately surface area of A0 size sheet is One Square Meter.