Составьте все возможные сумы и разности из чисел 5/6, 8/9, 11/12. найдите их значения. 30 .

1) 5/6 - 8/9 = 15/18 - 16/18 = -1/18
2) 5/6 - 11/12 = 10/12 - 11/12 = -1/12
3) 8/9 - 5/6 = 16/18 - 15/18 = 1/18
4) 8/9 - 11/12 = 32/36 - 33/36 = -1/36
5) 11/12 - 5/6 = 11/12 - 10/12 = 1/12
6) 11/12 - 8/9 = 33/36 - 32/36 = 1/36

7) 5/6 + 8/9 = 15/18 + 16/18 = 31/18 = 1 13/18
8) 5/6 + 11/12 = 10/12 + 11/12 = 21/12 = 1 9/12 = 1 3/4
9) 8/9 + 11/12 = 32/36 + 33/36 = 65/36 = 1 29/36