Ответ:

  1. \(1-\frac12=\frac22-\frac12=\frac12\).
  2. \(1-\frac29=\frac99-\frac29=\frac79\).
  3. \(1-\frac{2}{11}=\frac{11}{11}-\frac{2}{11}=\frac9{11}\).
  4. \(1-\frac5{12}=\frac{12}{12}-\frac5{12}=\frac7{12}\).
  5. \(1-\frac34=\frac44-\frac34=\frac14\).
  6. \(1-\frac59=\frac99-\frac59=\frac49\).
  7. \(4-\frac25=3+\frac55-\frac25=3\frac35\).
  8. \(3-\frac58=2+\frac88-\frac58=2\frac38\).
  9. \(8\frac56-1=7\frac56\).
  10. \(2\frac37-\frac37=2\).
  11. \(7-\frac59=6+\frac99-\frac59=6\frac49\).
  12. \(6-\frac78=5+\frac88-\frac78=5\frac18\).