• № 1. Выполните действия a) а) 7-45 = 9 6) 43+15 10 12 6) 613+29= 21 14 c) 51-32= 6 4 2) 11-(45+33) 6 10

a) $$7-4\frac{5}{9} = 6\frac{9}{9} - 4\frac{5}{9} = (6-4)+\frac{9-5}{9} = 2 + \frac{4}{9} = 2\frac{4}{9}$$

Ответ: $$2\frac{4}{9}$$

б) $$4\frac{3}{10}+1\frac{5}{12} = 4\frac{3 \cdot 6}{10 \cdot 6} + 1\frac{5 \cdot 5}{12 \cdot 5} = 4\frac{18}{60} + 1\frac{25}{60} = (4+1) + \frac{18+25}{60} = 5 + \frac{43}{60} = 5\frac{43}{60}$$

Ответ: $$5\frac{43}{60}$$

в) $$6\frac{13}{21}+2\frac{9}{14} = 6\frac{13 \cdot 2}{21 \cdot 2} + 2\frac{9 \cdot 3}{14 \cdot 3} = 6\frac{26}{42} + 2\frac{27}{42} = (6+2) + \frac{26+27}{42} = 8 + \frac{53}{42} = 8 + \frac{42+11}{42} = 8 + 1\frac{11}{42} = 9\frac{11}{42}$$

Ответ: $$9\frac{11}{42}$$

с) $$5\frac{1}{6}-3\frac{3}{4} = 5\frac{1 \cdot 2}{6 \cdot 2} - 3\frac{3 \cdot 3}{4 \cdot 3} = 5\frac{2}{12} - 3\frac{9}{12} = 4\frac{14}{12} - 3\frac{9}{12} = (4-3) + \frac{14-9}{12} = 1 + \frac{5}{12} = 1\frac{5}{12}$$

Ответ: $$1\frac{5}{12}$$

e) $$11-(4\frac{5}{6}+3\frac{3}{10}) = 11 - (4\frac{5 \cdot 5}{6 \cdot 5} + 3\frac{3 \cdot 3}{10 \cdot 3}) = 11 - (4\frac{25}{30} + 3\frac{9}{30}) = 11 - (4+3 + \frac{25+9}{30}) = 11 - (7 + \frac{34}{30}) = 11 - (7 + \frac{30+4}{30}) = 11 - (7 + 1\frac{4}{30}) = 11 - 8\frac{4}{30} = 10\frac{30}{30} - 8\frac{4}{30} = (10-8) + \frac{30-4}{30} = 2 + \frac{26}{30} = 2\frac{26}{30} = 2\frac{13}{15}$$

Ответ: $$2\frac{13}{15}$$