Odpowiedź:
2 i 1/7 + 5 i 6/7 = 7 i 7/7 = 8
2/13 + 1/13 = 3/13
7/10 + 8/10 = 15/10 = 1 i 5/10 = 1 i 1/2
12 i 8/10 + 3 i 2/10 = 15 i 10/10 = 16
1 - 3/12 = 12/12 - 3/12 = 9/12 = 3/4
1 - 6/20 = 20/20 - 6/20 = 14/20 = 7/10
5 - 3/7 = 4 i 7/7 - 3/7 = 4 i 4/7