Ответ:

  1. \(273+418=691\);
  2. \(426+357=783\);
  3. \(347+535=882\);
  4. \(635+158=793\);
  5. \(875-42=833\);
  6. \(369-27=342\);
  7. \(486-58=428\);
  8. \(753-36=717\).