Ответ:

  1. 8 + 9 = 17
  2. 15 + 3 = 18
  3. 11 + 4 = 15
  4. 20 − 9 = 11
  5. 19 + 1 = 20
  6. 14 + 6 = 20
  7. 14 − 8 = 6
  8. 17 − 4 = 13
  9. 18 − 6 = 12
  10. 6 + 16 = 22
  11. 12 + 5 = 17
  12. 17 + 2 = 19
  13. 19 − 6 = 13
  14. 9 − 4 = 5
  15. 23 − 8 = 15