1. 3/5; 1/7; 7/15; 4
2. а) 4/18 + 5/18 = 9/18 = 1/2
б) 51/60 - 25/60 = 26/60 = 13/30
в) 33/45 + 1/45 = 34/45 - 3/10 = 68/90 - 27/90 = 41/90
3. а) Х = 5/33 + 5/11 = 5/33 + 15/33 = 20/33
б) 3,48Х = 36,54
Х = 36,54/3,48 = 10,5
4. 7/15 - 1/12 = 28/60 - 5/60 = 23/60 второй день
7/15 + 23/60 = 28/60 + 23/60 = 51/60 = 17/20 за два дня
5. 5/7; 9/14; 11/14; 13/21