Question 320889
We have 26 black cards, 6 of them are face cards, 20 of them are not face cards. Of course.
a> here is the diagram, hope you can understand.
<---1st picking--->	<---2nd picking--->	<---3rd picking--->
face card: 6/10		face card: 5/25		face card: 4/24
						normal card: 20/24 
			normal card: 20/25	face card: 5/24
						normal card: 19/24
						
normal card: 20/26	face card: 6/25		face card: 5/24
						normal card: 19/24
			normal card: 19/25	face card: 6/24
						normal card: 18/24
b> The probability of one or more of three cards picked is face card = 1 - the probability of all the picked cards are normal cards.
You can see in the diagram that the probability of all the three picking are normal cards is: (20/26)(19/25)(18/24). 
So the finding probability is 1 - (20/26)(19/25)(18/24)
c>Actually, I dont really remember how to solve this kind of question :-( but I think that I would solve this way:
Given that you did get 1 face card -> the probability of getting two more face cards is: (5/25)(4/24)
Given that you did get 2 face cards -> the probability of getting one more face card is (4/24)
So, the probability of getting three face cards given that you get one or more face card is (5/25)(4/24) + (4/24).
I think I get the last solution wrong, so you should post the last problem again to get help from other tutors. I am sorry for this.