Ответ:

  1. \(8\times2=16\);
  2. \(24:3=8\);
  3. \(14:2=7\);
  4. \(3\times5=15\);
  5. \(42+18-40=60-40=20\);
  6. \(18+26+16=44+16=60\);
  7. \(80-34+16=46+16=62\);
  8. \(53+37-66=90-66=24\).