Ответ:

  1. \(513\cdot42=513\cdot(40+2)=20520+1026=21546\).
  2. \(608\cdot76=608\cdot(70+6)=42560+3648=46208\).
  3. \(5419\cdot42=5419\cdot(40+2)=216760+10838=227598\).
  4. \(6217\cdot960=6217\cdot(1000-40)=6217000-248680=5968320\).
  5. \(2154\cdot437=2154\cdot(400+30+7)=861600+64620+15078=941298\).
  6. \(302\cdot405=302\cdot(400+5)=120800+1510=122310\).

Ответ: 1) 21 546; 2) 46 208; 3) 227 598; 4) 5 968 320; 5) 941 298; 6) 122 310.