Ответ:

  1. \(101000_2=1\cdot2^5+1\cdot2^3=32+8=40_{10}\).

  2. \(111001{,}001_2=1\cdot2^5+1\cdot2^4+1\cdot2^3+1\cdot2^0+1\cdot2^{-3}=32+16+8+1+0.125=57.125_{10}\).

  3. \(100001011{,}101_2=1\cdot2^8+1\cdot2^3+1\cdot2^1+1\cdot2^0+1\cdot2^{-1}+1\cdot2^{-3}=256+8+2+1+0.5+0.125=267.625_{10}\).

Ответ: 1) 40; 2) 57,125; 3) 267,625.