2. Multiply each bit by its corresponding power of 2 and add all the terms up.
1 1011 0001 1001 1000(2) =
(1 × 216 + 1 × 215 + 0 × 214 + 1 × 213 + 1 × 212 + 0 × 211 + 0 × 210 + 0 × 29 + 1 × 28 + 1 × 27 + 0 × 26 + 0 × 25 + 1 × 24 + 1 × 23 + 0 × 22 + 0 × 21 + 0 × 20)(10) =
(65 536 + 32 768 + 0 + 8 192 + 4 096 + 0 + 0 + 0 + 256 + 128 + 0 + 0 + 16 + 8 + 0 + 0 + 0)(10) =
(65 536 + 32 768 + 8 192 + 4 096 + 256 + 128 + 16 + 8)(10) =
111 000(10)
The number 1 1011 0001 1001 1000(2) converted from an unsigned binary (in base 2) and written as a positive integer (with no sign) in decimal system (in base ten):
1 1011 0001 1001 1000(2) = 111 000(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.