Карточка №10 Найдите значение выражения: 1 23 1. 10 20 51 2. -+ 25 8 3. 5.4 1 4. 1+- 4 1 5. 1 + 36 45 8 135 6. + 33 22 7. (2-1):28 16 14 8. 41: 10+2 4 9. 9.(3) -19.2 10. 19 7 13 (一) 25 13 12

1. 1. \[\frac{1}{10} - \frac{23}{20} = \frac{2}{20} - \frac{23}{20} = -\frac{21}{20} = -1\frac{1}{20}\]

2. 2. \[\frac{5}{2} + \frac{1}{5} = \frac{25}{10} + \frac{2}{10} = \frac{27}{10} = 2.7\]

3. 3. \[5 \cdot 4 = 20\]

4. 4. \[1 + \frac{1}{4} = \frac{4}{4} + \frac{1}{4} = \frac{5}{4} = 1\frac{1}{4}\]

5. 5. \[\frac{1}{1} = 1\]

6. 6. \[\frac{1}{36} + \frac{1}{45} = \frac{5}{180} + \frac{4}{180} = \frac{9}{180} = \frac{1}{20}\]

   \[\frac{8}{33} + \frac{13}{22} = \frac{16}{66} + \frac{39}{66} = \frac{55}{66} = \frac{5}{6}\]

   \[\frac{5}{6} : \frac{1}{20} = \frac{5}{6} \cdot 20 = \frac{100}{6} = \frac{50}{3} = 16\frac{2}{3}\]

7. 7. \[2\frac{1}{16} - 1\frac{1}{14} = \frac{33}{16} - \frac{15}{14} = \frac{231}{112} - \frac{120}{112} = \frac{111}{112}\]

   \[\frac{111}{112} \cdot 28 = \frac{111}{4} = 27\frac{3}{4} = 27.75\]

8. 8. \[1\frac{1}{15} + \frac{3}{5} = \frac{16}{15} + \frac{9}{15} = \frac{25}{15} = \frac{5}{3}\]

   \[4 \frac{1}{4} : \frac{5}{3} = \frac{17}{4} \cdot \frac{3}{5} = \frac{51}{20} = 2.55\]

9. 9. \[\frac{1}{9} - 19 \frac{1}{9} = \frac{1}{9} - \frac{172}{9} = -\frac{171}{9} = -19\]

   \[9 \cdot (-19) = -171\]

10. 10. \[\frac{19}{25} - \frac{7}{13} = \frac{247}{325} - \frac{175}{325} = \frac{72}{325}\]

    \[\frac{72}{325} : \frac{13}{12} = \frac{72}{325} \cdot \frac{12}{13} = \frac{864}{4225} ≈ 0.2045\]

Ответ: См. решение