442.
1) Привести дроби к знаменателю 36.
1/2 = 18/36 и 3/4 = 27/36 и 5/6 = 30/36 и 7/9 =28/36 и 11/12 = 33/36 и 17/18 = 34/36
2) Привести дроби к знаменателю 42.
1/2 = 21/42 и 2/3 = 28/42 и 4/7 = 24/42 и 5/14 = 15/42 и 8/21 = 16/42 и 1/6 = 7/42
3) Привести дроби к знаменателю 56.
3/8 =21/56 и 5/7 = 40/56 и 1/4 = 14/56 и 1/14 = 4/56 и 13/28 = 26/56
4) Привести дроби к знаменателю 72.
4/8 = 36/72 и 2/9 = 16/72 и 1/6 = 12/72 и 5/12 = 30/72 и 11/18 = 44/72 и 7/36 = 14/72.