Числитель
1) 6 3/4 : 9 = 27/4 : 9 = 27/4 * 1/9 = 3/4
2) 24 : 6/7 = 24/1 * 7/6 = 28/1 = 28
3) 1/9 : 4/21 = 1/9 * 21/4 = 7/12
4) 3/4 + 28 = 28 3/4
5) 28 3/4 - 7/12 = 115/4 - 7/12 = 338/12 = 169/6
Знаменатель
1) 22 14/15 : 2 2/3 = 344/15 : 8/3 = 344/15 * 3/8 = 43/5
2) 53 2/3 - 43/5 =161/3 - 43/5 = 676/15
Результат
169/6 : 676/15 = 169/6 *15/676= 5/8
Ответ: 5/8