1.0 1/6 + （5/6-3/4）/ (2/5) = 1/6 + (20/24 - 18/24) / (2/5)= 1/6 + (2/24) / (2/5)= 1/6 + (2/24 * 5/2)= 1/6 + 5/24= 4/24 + 5/24 = 9 / 24 = 3 / 8 2.0 (4/5 * 1/4 ) + (3.2* 1/4) - (1 / 4) = (1/5) + (16/5...还有其他的呢？不过要全部的！