Ответ:

  1. 63 · 12 = 63 · (10 + 2) = 630 + 126 = 756.
  2. 114 · 9 = 114 · (10 − 1) = 1140 − 114 = 1026.
  3. 500 · 4 = 2000.
  4. 34 · 100 = 3400.
  5. 6243 + 2314 = 8557.
  6. 3718 − 527 = 3718 − 500 − 27 = 3218 − 27 = 3191.
  7. 2678 + 895 = 2678 + 900 − 5 = 3578 − 5 = 3573.
  8. 985 − 699 = 985 − 700 + 1 = 285 + 1 = 286.