Нужно решить пример по действиям (11,25-3 5/12+4,3-7 19/30) : (7 7/12-5 5/6)

1. 11,25 - 3 5/12 =
11 1/4 - 3 5/12 =
11 3/12 - 3 5/12 =
10 15/12 - 3 5/12 =
7 10/12 = 7 5/6
2. 7 5/6 + 4.3 =
7 5/6 + 4 3/10 =
7 25/30 + 4 9/30 =
11 34/30
3. 11 34/30 - 7 19/30 =
4 15/30 = 4 1/2 = 9/2
4. 7 7/12 - 5 5/6 =
7 7/12 - 5 10/12 =
6 19/12 - 5 10/12 =
1 9/12 = 1 3/4 = 7/4
5. 9/2 : 7/4 = 9/2 * 4/7 =
9*2/7 = 18/7 = 2 4/7

1) 11,25 - 3 (5/12) + 4,3 - 7 (19/30) = 15,55 - 3 ( 25/60 ) - 7 ( 38/60 ) = 15,55 - 10 ( 63/60 ) = 15,55 - 11 ( 1/20 ) = 15,55 - 11,05 = 4,5
2) 7 (7/12) - 5 (5/6 ) = 7 (7/12 ) - 5 (10/12 ) = 6 (19/12) - 5 (10/12) = 1 (9/12 ) = 1 (3/4)
3) 4,5 : 1 (3/4) = (9/2) : ( 7/4) = 18/7 = 2 ( 4/7 )
ответ 2 (4/7)