Decimal number is a number expressed in the base 10 numeral system. Decimal number’s digits have 10 symbols: 0,1,2,3,4,5,6,7,8,9. Each digit of a decimal number counts a power of 10. For binary number with n digits: dn-1 … d3 d2 d1 d0. The decimal number is equal to the sum of binary digits (d n) times their power of 2 (2 n):

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