Ответ:

  1. 900 - 688 : 4 = 900 - 172 = 728
  2. (900 - 688) : 4 = 212 : 4 = 53
  3. 369 - 2 : 3 = 369 - (2/3) = 369 - 0.666... ≈ 368.33
  4. 328 - 3 : 8 = 328 - (3/8) = 328 - 0.375 = 327.625
  5. (90 + 60) - 5 - 0 = 150 - 5 - 0 = 145
  6. 660 - 60 : 6 - 1 = 660 - 10 - 1 = 649