How do you convert hexa into decimal? - Answers

I presume by hexa you mean hexadecimal, which is base 16. A hexadecimal number can be considered a polynomial in a variable whose value is 16, the coefficients being whole numbers ranging from 0 to 15. The hexadecimal digits after 9 are usually written as the letters A through F (sometimes in lower case); A means 10, B means 11, and so on. Just plug in 16 for the variable and evaluate the polynomial. For example, consider the hexadecimal number 3E7. The 7 is in the units place, the E, meaning 14, is in the 16's place, and the 3 is in the 162 (256) place. So the value of this number, in decimal, is 3 x 256 + 14 x 16 + 7, which works out to be 999 (so help me, I picked those digits at random!).