Ответ:

  1. 2/4 = 1/2.
  2. 7/28 = 1/4.
  3. 6/20 = 3/10.
  4. 24/56 = 3/7.
  5. 42/98 = 3/7.
  6. 18/81 = 2/9.
  7. 60/156 = 5/13.
  8. 300/450 = 2/3.