Ответ:

  1. \((25 \cdot 4) \cdot 7 = 100 \cdot 7 = 700\).
  2. \(832 - 328 - 247 = 504 - 247 = 257\).
  3. \(903 - (178 + 359) = 903 - 537 = 366\).
  4. \((300 : 3) \cdot 6 = 100 \cdot 6 = 600\).
  5. \(603 - (347 - 189) = 603 - 158 = 445\).
  6. \(324 + (503 - 299) = 324 + 204 = 528\).

Ответ: 700; 257; 366; 600; 445; 528.