1. Вычислите: 1) 0,5 · 4; 2) 13/25 − 4/30; 3) 4/15 + 2/3.

1. \(0.5\cdot4=2\).
2. \(\frac{13}{25}-\frac{4}{30}=\frac{78}{150}-\frac{20}{150}=\frac{58}{150}=\frac{29}{75}\).
3. \(\frac{4}{15}+\frac{2}{3}=\frac{4}{15}+\frac{10}{15}=\frac{14}{15}\).

Ответ: 1) 2; 2) \(\frac{29}{75}\); 3) \(\frac{14}{15}\).