I still don't know how to do permutation/combination problem

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Help me out with this problem:

A family consisting of one mother, one father, two daughters and a son is taking a road trip in a sedan. The sedan has two front seats and three back seats. If one of the parents must drive and the two daughters refuse to sit next to each other, how many possible seating arrangements are there?


28

32

48

60

120


Let me know the method. I thought n!/(n-r), but not sure.
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by shamz » Sun Oct 19, 2008 8:59 am
What is the given answer? Is it 28?

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by gmat800master » Mon Oct 20, 2008 4:30 pm
If you are looking for information on combinatorics (permutations or combinations), then here are my suggestions:

(1) Go out to Math world's website here
(2) View Combinations - GMAT Study Guide
(3) Go out to Math Warehouse's explanation here

Then, once you have this down, just go and work a bunch of problems.

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by sreedharavula » Wed Oct 22, 2008 11:37 pm
I think it is 32. what is the answer given?

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by lachlanc » Wed Nov 12, 2008 6:30 pm
does anyone have an answer to this question?

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by logitech » Wed Nov 12, 2008 7:24 pm
Guys today the fish is on me:

https://www.beatthegmat.com/mgmat-cat-pe ... 20320.html

But please learn how to fish:

1) Copy paste the question stem to search bar here and check whether the question discussed before

2) There is this amazing website called GOOGLE and you can use the same method here.


Thanks!
LGTCH
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"DON'T LET ANYONE STEAL YOUR DREAM!"

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by lachlanc » Thu Nov 13, 2008 7:12 am
Hey Logitech,

Just as you have a problem with IM English, I have a problem with condescending douche-bag comments like that.

Thanks!

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by logitech » Thu Nov 13, 2008 9:33 am
lachlanc wrote:Hey Logitech,

Just as you have a problem with IM English, I have a problem with condescending douche-bag comments like that.

Thanks!
Did I break your heart ? Sorry
LGTCH
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"DON'T LET ANYONE STEAL YOUR DREAM!"