Ответ:

  1. 70000 + 600 = 70600.
  2. 38000 − 30000 = 8000.
  3. 64500 − 500 = 64000.
  4. 726000 − 20000 = 706000.
  5. 20000 + 800 + 6 = 20806.
  6. 300000 + 10000 + 400 = 310400.