Numerical constants (π, e, ½) do not have significant digits. For example, the volume of sphere is calculated with the formula V = ^{4}/_{3} πr^{3}. Using this formula, a sphere with a measured diameter of 24 cm would have a volume equal to^{4}/_{3} π(12)^{3} = ^{4}/_{3} π(1728) = 2304π cm^{3} Since 12 only had two significant digits, your final value for the sphere's volume should only have 2 SD. This means that a calculated value of V = 7238.229 cm^{3} should be expressed in final form as7200 cm^{3} = 7.2 x 10^{3} cm^{3}

(1) When the absolute value of the original number is greater than one, then moving the decimal point will require the resulting number to be multiplied by 10 raised to a positive exponent.

(2) When the absolute value of the original number is less than one, then moving the decimal point will require the resulting number to be multiplied by 10 raised to a negative exponent.