2. Вычислите: 1) 8 + 4/15 2) 4/9 + 3/7 3) 1 - 14/23 4) 6 - 3/9

Решение:

1. \( 8 + \frac{4}{15} = \frac{8 \cdot 15}{15} + \frac{4}{15} = \frac{120 + 4}{15} = \frac{124}{15} \)
2. \( \frac{4}{9} + \frac{3}{7} = \frac{4 \cdot 7 + 3 \cdot 9}{9 \cdot 7} = \frac{28 + 27}{63} = \frac{55}{63} \)
3. \( 1 - \frac{14}{23} = \frac{23}{23} - \frac{14}{23} = \frac{23 - 14}{23} = \frac{9}{23} \)
4. \( 6 - \frac{3}{9} = 6 - \frac{1}{3} = \frac{6 \cdot 3}{3} - \frac{1}{3} = \frac{18 - 1}{3} = \frac{17}{3} \)

Ответ: 1) \(\frac{124}{15}\); 2) \(\frac{55}{63}\); 3) \(\frac{9}{23}\); 4) \(\frac{17}{3}\).