1. Вычислить: 1) -3\frac{1}{8} \cdot 16 2) -2,84 - 5,49 3) 2 - (-6) - 8 4) -2\frac{4}{15} : (-1,7) 5) 3\frac{3}{4} - 5\frac{5}{6}

Решение:

1. 1) \[-3\frac{1}{8} \cdot 16 = -\frac{25}{8} \cdot 16 = -25 \cdot 2 = -50\]
2. 2) \[-2,84 - 5,49 = -8,33\]
3. 3) \[2 - (-6) - 8 = 2 + 6 - 8 = 8 - 8 = 0\]
4. 4) \[-2\frac{4}{15} : (-1,7) = -\frac{34}{15} : (-\frac{17}{10}) = -\frac{34}{15} \cdot (-\frac{10}{17}) = \frac{34}{15} \cdot \frac{10}{17} = \frac{2 \cdot 17}{3 \cdot 5} \cdot \frac{2 \cdot 5}{17} = \frac{2}{3} \cdot 2 = \frac{4}{3} = 1\frac{1}{3}\]
5. 5) \[3\frac{3}{4} - 5\frac{5}{6} = \frac{15}{4} - \frac{35}{6} = \frac{15 \cdot 3}{12} - \frac{35 \cdot 2}{12} = \frac{45 - 70}{12} = -\frac{25}{12} = -2\frac{1}{12}\]

Ответ: 1) -50; 2) -8,33; 3) 0; 4) 1\frac{1}{3}; 5) -2\frac{1}{12}