Ответ:

а) НОЗ(3, 9) = 9:

\(\frac{1}{3}=\frac{3}{9}\). Получаем \(\frac{3}{9}\) и \(\frac{1}{9}\).

б) НОЗ(4, 6) = 12:

\(\frac{1}{4}=\frac{3}{12}\), \(\frac{5}{6}=\frac{10}{12}\).

в) НОЗ(21, 15) = 105:

\(\frac{8}{21}=\frac{40}{105}\), \(\frac{13}{15}=\frac{91}{105}\).

г) НОЗ(72, 48) = 144:

\(\frac{32}{72}=\frac{64}{144}\), \(\frac{11}{48}=\frac{33}{144}\).

Ответ: а) \(\frac{3}{9}\) и \(\frac{1}{9}\); б) \(\frac{3}{12}\) и \(\frac{10}{12}\); в) \(\frac{40}{105}\) и \(\frac{91}{105}\); г) \(\frac{64}{144}\) и \(\frac{33}{144}\).