利用乘法分配律=(36-1)×5/36=36*5/36-1*5/36=5-5/36=4又31/36
=(36-1)x5/36=36x5/36-5/36=5-5/36
=(36-1)Ⅹ5/36=36Ⅹ5/36-1X5/36=5-5/36=175/36