Ответ:
- \(2\frac{1}{3}\cdot9=21\), \(1\frac{1}{3}\cdot3\frac{1}{4}=\frac{4}{3}\cdot\frac{13}{4}=\frac{13}{3}\), \(2\frac{2}{7}\cdot3\frac{5}{24}=\frac{16}{7}\cdot\frac{77}{24}=\frac{22}{3}\). Поэтому \(21-\frac{13}{3}-\frac{22}{3}=\frac{28}{3}=9\frac{1}{3}\).
- \(1\frac{7}{48}\cdot2\frac{2}{5}=\frac{55}{48}\cdot\frac{12}{5}=\frac{11}{4}\). В скобках: \(9\frac{1}{6}\cdot\frac{4}{15}=\frac{55}{6}\cdot\frac{4}{15}=\frac{22}{9}\), значит \(\frac{22}{9}+2\frac{5}{9}=\frac{49}{9}\), а \(\frac{49}{9}\cdot\frac{2}{5}=\frac{98}{45}\). Получаем \(\frac{11}{4}-\frac{98}{45}=\frac{299}{180}=1\frac{119}{180}\).
- \(2\frac{1}{4}+4\frac{5}{6}=\frac{27}{4}\), \(\frac{27}{4}:3\frac{2}{5}=\frac{27}{4}:\frac{17}{5}=\frac{135}{68}\), \(\frac{3}{4}:\frac{3}{5}=\frac{5}{4}\). Ответ: \(\frac{135}{68}-\frac{5}{4}=\frac{125}{68}=1\frac{57}{68}\).
- \(3{,}04:\frac{1}{30}=91{,}2\), \(16{,}03:\frac{7}{20}=45{,}8\). Тогда \((91{,}2-45{,}8)\cdot\frac15+0{,}072\cdot\frac13=9{,}08+0{,}024=9{,}104\).
- \(-28{,}6:57{,}2=-0{,}5\), \(2{,}68:(-1{,}34)=-2\). Выражение равно \((-0{,}5-(-2))\cdot(-3{,}2)=1{,}5\cdot(-3{,}2)=-4{,}8\).
- \(3{,}64:(-1{,}4)=-2{,}6\), поэтому \(-1{,}7-2{,}6=-4{,}3\). Далее \((-4{,}3):(-0{,}001)=4300\), \(4300\cdot(-0{,}4)=-1720\).
- \(\frac{9}{14}+\frac{5}{21}=\frac{37}{42}\), \(-2\frac{9}{14}=-\frac{37}{14}\). Поэтому \(\frac{37}{42}:(-\frac{37}{14})=-\frac13\).
- \(\frac{7}{16}-\frac{31}{40}=\frac{35-62}{80}=-\frac{27}{80}\), \(-\frac{17}{24}+\frac{27}{40}=\frac{-85+81}{120}=-\frac{1}{30}\). Ответ: \((-\frac{27}{80}):(-\frac{1}{30})=\frac{81}{8}=10\frac18\).
- \((-4{,}5):\frac{9}{14}=-7\), значит \(-8\frac29-(-7)=-\frac{11}{9}\). Далее \(-\frac{11}{9}\cdot2\frac14=-\frac{11}{4}\), и \(-3\frac34-(-\frac{11}{4})=-\frac{15}{4}+\frac{11}{4}=-1\).
Ответ: 1) \(9\frac13\); 2) \(1\frac{119}{180}\); 3) \(1\frac{57}{68}\); 4) \(9{,}104\); 5) \(-4{,}8\); 6) \(-1720\); 7) \(-\frac13\); 8) \(10\frac18\); 9) \(-1\).
