Ответ:

  1. $$17 + 7 = 24$$
  2. $$24 + 9 = 33$$
  3. $$47 - 9 = 38$$
  4. $$41 - 3 = 38$$
  5. $$60 - 24 = 36$$
  6. $$70 - 53 = 17$$
  7. $$90 - (32 + 8) = 90 - 40 = 50$$
  8. $$70 + (60 - 40) = 70 + 20 = 90$$