✔ 最佳答案
ai. 4/6 * 3/5 * 2/4 * 1/3 = 1/15
First, you guess one colour from 6 choices. There are 4 correct answer so P(correct) = 4/6. Now there are 5 pigs left and you still need to guess 3 colours. P(correct) = 3/5. 如此類推...
aii. This is conditional probability. The probability should be P(條件A AND 條件B) / P(條件B), where B is the given situation.
B is the same as Qs ai so
P(條件B) =ans from ai.
P(條件A AND 條件B) means you need to get both ORDER and COLOUR correct.
豬因為顏色不同, 所以有分次序, which means order matters. Therefore use P. Selecting 4 from 6, so total permutation = 6P4. Since the colours are unique, therefore when you guess, you only have one choice. For example, the correct order is Red > Blue > Yellow > Green. Then the correct guess can only be Red > Blue > Yellow > Green. Therefore numerator is 1.
So ans shd be 1/(6P4) / (1/15) = 1/24
I am sorry I can't type Chinese.