2. Multiply each bit by its corresponding power of 2 and add all the terms up.
1010 1010 1010 1010 1010 1010 1010 1010 1010 1010 1010 1010 1010(2) =
(1 × 251 + 0 × 250 + 1 × 249 + 0 × 248 + 1 × 247 + 0 × 246 + 1 × 245 + 0 × 244 + 1 × 243 + 0 × 242 + 1 × 241 + 0 × 240 + 1 × 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 + 0 × 222 + 1 × 221 + 0 × 220 + 1 × 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 + 1 × 25 + 0 × 24 + 1 × 23 + 0 × 22 + 1 × 21 + 0 × 20)(10) =
(2 251 799 813 685 248 + 0 + 562 949 953 421 312 + 0 + 140 737 488 355 328 + 0 + 35 184 372 088 832 + 0 + 8 796 093 022 208 + 0 + 2 199 023 255 552 + 0 + 549 755 813 888 + 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 + 0 + 2 097 152 + 0 + 524 288 + 0 + 131 072 + 0 + 32 768 + 0 + 8 192 + 0 + 2 048 + 0 + 512 + 0 + 128 + 0 + 32 + 0 + 8 + 0 + 2 + 0)(10) =
(2 251 799 813 685 248 + 562 949 953 421 312 + 140 737 488 355 328 + 35 184 372 088 832 + 8 796 093 022 208 + 2 199 023 255 552 + 549 755 813 888 + 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 + 2 097 152 + 524 288 + 131 072 + 32 768 + 8 192 + 2 048 + 512 + 128 + 32 + 8 + 2)(10) =
3 002 399 751 580 330(10)
The number 1010 1010 1010 1010 1010 1010 1010 1010 1010 1010 1010 1010 1010(2) converted from an unsigned binary (in base 2) and written as a positive integer (with no sign) in decimal system (in base ten):
1010 1010 1010 1010 1010 1010 1010 1010 1010 1010 1010 1010 1010(2) = 3 002 399 751 580 330(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.