Ответ:
- \(513\cdot42=513\cdot(40+2)=20\,520+1\,026=21\,546\).
- \(608\cdot76=608\cdot(70+6)=42\,560+3\,648=46\,208\).
- \(549\cdot42=549\cdot(40+2)=21\,960+1\,098=23\,058\).
- \(627\cdot960=627\cdot(96\cdot10)=(60\,192)\cdot10=601\,920\).
- \(2154\cdot437=2154\cdot(400+30+7)=861\,600+64\,620+15\,078=941\,298\).
- \(302\cdot405=302\cdot(400+5)=120\,800+1\,510=122\,310\).
Ответ: 1) 21 546; 2) 46 208; 3) 23 058; 4) 601 920; 5) 941 298; 6) 122 310.
