a) $$1/8 = 1/2 \cdot 1/4$$
б) $$5/9 = 5/3 \cdot 1/3$$
в) $$15/14 = 5/7 \cdot 3/2$$
г) $$1 \frac{7}{18} = \frac{25}{18} = \frac{5}{6} \cdot \frac{5}{3}$$
Ответ: a) 1/2 ⋅ 1/4; б) 5/3 ⋅ 1/3; в) 5/7 ⋅ 3/2; г) 5/6 ⋅ 5/3