GMAT Prep PS - C/P/P

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by krusta80 » Sat Mar 03, 2012 4:35 pm
myfish wrote:I tried to figure this one out. Somehow this question confuses me. Please take a crack at it and let me know. Thanks a lot!!
This is just a simple combination formula at work.

12 slots to choose from for 4 restaurants...

12C4 = 495 ways

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by myfish » Sat Mar 03, 2012 8:00 pm
That is beautifully embarrassing. I tried this over and over with that same formula, even during the test. 12!/4!8! I tried to simplify the fraction and lost it somehow. Very strange. I am doing too much!!!! Hahahaha Thanks again!



[quote="krusta80"][quote="myfish"]I tried to figure this one out. Somehow this question confuses me. Please take a crack at it and let me know. Thanks a lot!![/quote]

This is just a simple combination formula at work.

12 slots to choose from for 4 restaurants...

12C4 = 495 ways[/quote]

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by krusta80 » Sat Mar 03, 2012 10:13 pm
myfish wrote:That is beautifully embarrassing. I tried this over and over with that same formula, even during the test. 12!/4!8! I tried to simplify the fraction and lost it somehow. Very strange. I am doing too much!!!! Hahahaha Thanks again!


krusta80 wrote:
myfish wrote:I tried to figure this one out. Somehow this question confuses me. Please take a crack at it and let me know. Thanks a lot!!
This is just a simple combination formula at work.

12 slots to choose from for 4 restaurants...

12C4 = 495 ways
It happens! The good thing is that you had the right formula. I always cancel out the biggest factorial on the bottom with the last however-many terms of the top factorial and work from there.