Odpowiedź:
(2/3 + 5/6) : 3 - (7/9 - 1/2) = (4/6 + 5/6) : 3 - (14/18 - 9/18) = 9/6 : 3 - 5/18 = 9/6 * 1/3 - 5/18 = 3/6 - 5/18 = 9/18 - 5/18 = 4/18 = 2/9
2 i 7/12 - 2/3 : 8 + 7/8 = 2 i 7/12 - 2/3 * 1/8 + 7/8 = 2 i 7/12 - 1/12 + 7/8 = 2 i 6/12 + 7/8 = 2 i 12/24 + 21/24 = 2 i 33/24 = 3 i 9/24 = 3 i 3/8