- \(12\frac{4}{7}+6\frac{3}{5}=18+\frac{20}{35}+\frac{21}{35}=18\frac{41}{35}=19\frac{6}{35}\).
- \(18\frac{9}{11}-34\frac{2}{11}=\frac{207}{11}-\frac{376}{11}=-\frac{169}{11}=-15\frac{4}{11}\).
- \(16\frac{1}{5}\cdot\frac{20}{27}=\frac{81}{5}\cdot\frac{20}{27}=12\).
- \(3\frac{2}{13}\cdot2\frac{33}{78}=\frac{41}{13}\cdot\frac{63}{26}=\frac{3\cdot63}{26}=\frac{189}{26}=7\frac{7}{26}\).
- \(83{,}6:7{,}09=8360:709=\frac{8360}{709}\approx11{,}7913\).
- \(192{,}128:63{,}2=\frac{1921{,}28}{632}=3{,}04\).
- \(-|12{,}3|+2{,}5^2-|-1{,}9|=-12{,}3+6{,}25-1{,}9=-7{,}95\).
Ответ: а) \(19\frac{6}{35}\); б) \(-15\frac{4}{11}\); в) \(12\); г) \(7\frac{7}{26}\); д) \(\frac{8360}{709}\approx11{,}7913\); е) \(3{,}04\); ж) \(-7{,}95\).