The radius of a circle is stated as 2.12 cm. Its area should be written as

Area of a circle is given by A = π × , π =3.141. Since the minimum number of significant digits is three in this multiplication, the result should also be rounded off to three significant digits. A = 14.1124 cm²=14.1 cm²

Third Significant digit is 1 and next to it is also 1 which is less than 5, so the fourth digit onwards will be dropped off and rounded off to three significant digits 14.1 cm².