Ответ:

  1. 7 5/6 − 3 2/3 = 4 + 1/6 = 4 1/6.

  2. 8 5/12 − 6 7/20 = 2 + 25/60 − 21/60 = 2 1/15.

  3. 11 11/12 − 5 7/9 = 6 + 33/36 − 28/36 = 6 5/36.

  4. 9 17/24 − 8 11/36 = 1 + 51/72 − 22/72 = 1 29/72.