\[\frac{7}{15} \cdot 5 = \frac{7 \cdot 5}{15} = \frac{7 \cdot 1}{3} = \frac{7}{3} = 2\frac{1}{3}\]
б)\[\frac{5}{18} \cdot 12 = \frac{5 \cdot 12}{18} = \frac{5 \cdot 2}{3} = \frac{10}{3} = 3\frac{1}{3}\]
Ответ: а) \(2\frac{1}{3}\); б) \(3\frac{1}{3}\)