2. Multiply each bit by its corresponding power of 2 and add all the terms up.
11 0011 1011 0101 0101 0101 0010 1010 1010 1010 1101 0010 1010 1010 1000 1111(2) =
(1 × 261 + 1 × 260 + 0 × 259 + 0 × 258 + 1 × 257 + 1 × 256 + 1 × 255 + 0 × 254 + 1 × 253 + 1 × 252 + 0 × 251 + 1 × 250 + 0 × 249 + 1 × 248 + 0 × 247 + 1 × 246 + 0 × 245 + 1 × 244 + 0 × 243 + 1 × 242 + 0 × 241 + 1 × 240 + 0 × 239 + 0 × 238 + 1 × 237 + 0 × 236 + 1 × 235 + 0 × 234 + 1 × 233 + 0 × 232 + 1 × 231 + 0 × 230 + 1 × 229 + 0 × 228 + 1 × 227 + 0 × 226 + 1 × 225 + 0 × 224 + 1 × 223 + 1 × 222 + 0 × 221 + 1 × 220 + 0 × 219 + 0 × 218 + 1 × 217 + 0 × 216 + 1 × 215 + 0 × 214 + 1 × 213 + 0 × 212 + 1 × 211 + 0 × 210 + 1 × 29 + 0 × 28 + 1 × 27 + 0 × 26 + 0 × 25 + 0 × 24 + 1 × 23 + 1 × 22 + 1 × 21 + 1 × 20)(10) =
(2 305 843 009 213 693 952 + 1 152 921 504 606 846 976 + 0 + 0 + 144 115 188 075 855 872 + 72 057 594 037 927 936 + 36 028 797 018 963 968 + 0 + 9 007 199 254 740 992 + 4 503 599 627 370 496 + 0 + 1 125 899 906 842 624 + 0 + 281 474 976 710 656 + 0 + 70 368 744 177 664 + 0 + 17 592 186 044 416 + 0 + 4 398 046 511 104 + 0 + 1 099 511 627 776 + 0 + 0 + 137 438 953 472 + 0 + 34 359 738 368 + 0 + 8 589 934 592 + 0 + 2 147 483 648 + 0 + 536 870 912 + 0 + 134 217 728 + 0 + 33 554 432 + 0 + 8 388 608 + 4 194 304 + 0 + 1 048 576 + 0 + 0 + 131 072 + 0 + 32 768 + 0 + 8 192 + 0 + 2 048 + 0 + 512 + 0 + 128 + 0 + 0 + 0 + 8 + 4 + 2 + 1)(10) =
(2 305 843 009 213 693 952 + 1 152 921 504 606 846 976 + 144 115 188 075 855 872 + 72 057 594 037 927 936 + 36 028 797 018 963 968 + 9 007 199 254 740 992 + 4 503 599 627 370 496 + 1 125 899 906 842 624 + 281 474 976 710 656 + 70 368 744 177 664 + 17 592 186 044 416 + 4 398 046 511 104 + 1 099 511 627 776 + 137 438 953 472 + 34 359 738 368 + 8 589 934 592 + 2 147 483 648 + 536 870 912 + 134 217 728 + 33 554 432 + 8 388 608 + 4 194 304 + 1 048 576 + 131 072 + 32 768 + 8 192 + 2 048 + 512 + 128 + 8 + 4 + 2 + 1)(10) =
3 725 977 908 461 873 807(10)
The number 11 0011 1011 0101 0101 0101 0010 1010 1010 1010 1101 0010 1010 1010 1000 1111(2) converted from an unsigned binary (in base 2) and written as a positive integer (with no sign) in decimal system (in base ten):
11 0011 1011 0101 0101 0101 0010 1010 1010 1010 1101 0010 1010 1010 1000 1111(2) = 3 725 977 908 461 873 807(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.