Ответ:

  1. \((a+546)-328=a+218\).
  2. \((c+981)-592=c+389\).
  3. \((151+b)-109=b+42\).
  4. \(272-(125+y)=147-y\).
  5. \(925-(p+785)=140-p\).
  6. \(707-(n+634)=73-n\).