Пошаговое объяснение:
3/7 : 15/19 = 3/7 * 19/15 = 1/7 * 19/5 = 19/35
15/19:5 = 15 : 19/5 = 15 * 5/19 = 75/19 = 3 18/19
6 : 21 = 6/21 = 2/7
Пошаговое объяснение:
3/7 : 15/19 = 3/7 * 19/15 = 1/7 * 19/5 = 19/35
15/19:5 = 15 : 19/5 = 15 * 5/19 = 75/19 = 3 18/19
6 : 21 = 6/21 = 2/7