Question

what is positional number system

Answer 1

Positional notation denotes usually the extension to any base of the Hindu–Arabic numeral system. More generally, a positional system is a numeral system in which the contribution of a digit to the value of a number is the product of the value of the digit by a factor determined by the position of the digit. 

Answer 2

it is a numeral system in which the contribution of digit to the value of no . is the product of the value of digit by a factor determined by the position of the digit .