Вариант 2. №1. Вычислите: 1) 2 \(\frac{3}{5}\) \(\frac{25}{26}\) + 2 \(\frac{1}{4}\) \(\frac{27}{16}\) - 3 \(\frac{5}{6}\); 2) -2,4 \(\cdot\) 3 + 0,21: 0,07 + 15 \(\cdot\) (-0,3) + 9,7; 3) 8 + |4 - 52| - 2 \(\cdot\) |4,3 + 9,7|.

Решение:

1. \(2\frac{3}{5} \cdot \frac{25}{26} + 2\frac{1}{4} \cdot \frac{27}{16} - 3\frac{5}{6}\) = \(\frac{13}{5} \cdot \frac{25}{26} + \frac{9}{4} \cdot \frac{27}{16} - \frac{23}{6}\) = \(\frac{1}{1} \cdot \frac{5}{2} + \frac{243}{64} - \frac{23}{6}\) = \(\frac{5}{2} + \frac{243}{64} - \frac{23}{6}\) = \(\frac{5 \cdot 192}{384} + \frac{243 \cdot 6}{384} - \frac{23 \cdot 64}{384}\) = \(\frac{960 + 1458 - 1472}{384}\) = \(\frac{946}{384}\) = \(\frac{473}{192}\) = \(2\frac{89}{192}\)
2. \(-2,4 \cdot 3 + 0,21 : 0,07 + 15 \cdot (-0,3) + 9,7\) = \(-7,2 + 3 - 4,5 + 9,7\) = \(-7,2 + 3 - 4,5 + 9,7\) = \(-4,2 - 4,5 + 9,7\) = \(-8,7 + 9,7\) = \(1\)
3. \(8 + |4 - 52| - 2 \cdot |4,3 + 9,7|\) = \(8 + |-48| - 2 \cdot |14|\) = \(8 + 48 - 2 \cdot 14\) = \(8 + 48 - 28\) = \(56 - 28\) = \(28\)

Ответ: 1) \(2\frac{89}{192}\); 2) 1; 3) 28.