您好，問題如下，有些冗長不好意思
Q: A pair of dice, one red and the other green, is rolled six times. We know
that the ordered pairs (1, 1), (1, 5), (2, 4), (3, 6), (4, 2), (4, 4), (5,
1), and (6, 3) did not come up. What is the probability that every value came
up on both the red die and the green one?
A:
題目說擲六次中，紅色和綠色的點數{1, 2, 3, 4, 5, 6}都要出現。理解為這是A->B
一對一對的關係，但是又要扣掉禁位的pairs。
所以這是這是紅綠骰子的禁位表格
a1 表示出現點數對(1, 1)(1, 5)
a2