Question

1. What is the decimal expansion of the number with hexadecimal expansion (2AC)? Answer the integer.

2. Convert the binary expansion 10011000011 to hexadecimal expansion.

Answer 1

Part 1 :
2AC:

In decimal = C* 16⁰ + A*16¹ +2*16²
  = 12* 16⁰ + 10*16¹ +2*16² [ As C=12 and A=10 ]
=12*1 +10*16+2*256
=684

Therefore, 2AC in decimal = 684

Part 2:

10011000011
Split it into parts such that eah part contains 4 bits.
100 1100 0011 [ As first contains only 3 bits so we can append 1 bit as 0 so its valuse will remain the same and we will have four bits as well]
100 1100 0011 = 0100 1100 0011
Now convert each four bits into hexadecimal [ i.e.  0011 = 3, 1100 =12 =C and 0100 =4 ]
Therefore, in hexadecimal = 4C3