Question

what do you mean by significant digits. explain addtion and subtraction of quantities using idea of significant figures.​

Answer 1

The significant figures (also known as the significant digits or precision) of a number written in positional notation are digits that carry meaningful contributions to its measurement resolution. Of the significant figures in a number, the most significant is the position with the highest exponent value (the left-most in normal decimal notation), and the least significant is the position with the lowest exponent value (the right-most in normal decimal notation). For example, in the number "123", the "1" is the most significant figure as it counts hundreds (10²), and "3" is the least significant figure as it counts ones (10⁰).