Ответ:

  1. \(50:2,5=20\)
  2. \(500:2,5=200\)
  3. \(19,6+7,89=27,49\)
  4. \(5-2,13=2,87\)
  5. \(9,73-8,3=1,43\)
  6. \(\frac{1}{6}+\frac{1}{5}=\frac{11}{30}\)
  7. \(\frac{1}{3}+\frac{3}{4}=\frac{13}{12}=1\frac{1}{12}\)
  8. \(2\frac{3}{8}-\frac{1}{4}=2\frac{1}{8}\)
  9. \(7,517\cdot100=751,7\)
  10. \(92,6:1000=0,0926\)

Ответ: 11) 20; 12) 200; 13) 27,49; 14) 2,87; 15) 1,43; 16) \(\frac{11}{30}\); 17) \(1\frac{1}{12}\); 18) \(2\frac{1}{8}\); 19) 751,7; 20) 0,0926.