Number of possible outfits and arrangements

skyefall

New member
Joined
Nov 12, 2008
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I've been trying to answer this question for ages now, but for some reason I just can't make my answer match the choices.

Five different outfits are to be displayed in a store window. From 5 different winter outfits, 3 must be chosen, and from 4 different fall outfits, 2 must be chosen. These outfits will then be arranged in a row in the store window. The number of displays that can be made by choosing the outfits and then arranging them in the window is
a. 300
b. 3 600
c. 7 200
d. 86 400

I (believe) I have solved the first part of the question (the number of possible outfits); 5C3 x 4C2 = 60
But the second part about arranging them. I've tried 5!/3!2! because there are 3 identical values & 2 identical values (the winter outfits & the fall outfits). This = 10, but none of the choices are 600.
Am I completely off track here? I'd appreciate any help you can give.

EDIT: I've just tried 5! to solve the second part which = 120. 120 x 60 = 7200. I'm really doubting myself right now though, so if someone can verify it for me?
 
Total choices of five: C(5, 3) * C(4, 2) = 10 * 6 = 60

Total arrangements of any one set of five choices (assuming in a row, such as in a window display): P(5, 5) = 120

Total arrangements of total choices: (120)(60) = 7200

...but I'm not very good at these, so if somebody else proffers another solution (sensibly explained, of course), you should probably go with that.... :oops:

Eliz.
 
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