PLEASE HELP: How many ways are there to choose 3 cards from a standard deck of 52, if all three cards must be different suits? (Assume that the order of the cards don't matter)
How many suits are there in a deck of cards?
4 Suits
13 cards per suit
How many ways are there to choose 3 of the 4 suits?
(That's the first step)
4 c 3 = 4
good
Now, the second step is to determine how many ways there are to choose a card of one suit. First, how many cards of there of a suit?
13
How many ways are there to choose one of those 13 cards?
One of thirteen? Well, 1, 13 c 1, if you want.
13c1 = 13 ways to choose 1 of 13 cards.
Whoops, xD
My mistake, I meant 13.
Now repeat the process twice more. How many ways are there to pick a card of a second suit? A third suit?
Wouldn't it also be 13 for the second suit and 13 for the third suit?
Yes!
Now, use the fundamental counting principle to tell me. How many ways are there to pick 3 different suits and then pick one card from each of those three suits?
What does the fundamental counting principle tell us about how to count the total number ways to do something?
To multiply your choices? (per say)
Yes!
So I think it would be (4 c 3) x (3 c 1) = 12, or 4 x 3 = 12
Partly correct. Partly incorrect. 4 c 3 is good. 3 c 1 is not good.
The 4 c 3 part is choosing the three suits. 3 c 1 is not necessary for that.
Really just multiply all the numbers we got together (4,13,13,13)
So 8788?
Yes.
Because you have 4 cases (of picking 3 suits out of 4) and then you have a choice of 13 cards to "represent" each suit?
13^3*
13 for each suit
yes. 13 cards to represent each suit, three times. yes 13^3
Okay, alright, thanks a ton.
np
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