1. ## Probability (help please!)

I'm going over stuff for the final, but I can't figure out how they did this...

I tried hypergeometric distribution, but my answer was way off from the answer key... !

[img]http://i47.tinypic.com/2h2dsuf.png[/img]

Thank you...

2. ## Re: Probability (help please!)

Originally Posted by PennCow
I'm going over stuff for the final, but I can't figure out how they did this...

I tried hypergeometric distribution, but my answer was way off from the answer key.
[img]http://i47.tinypic.com/2h2dsuf.png[/img]
$\displaystyle \frac{\binom{7}{4}\binom{11}{1}}{\binom{18}{5}}=0. 044934640522876$

3. ## Re: Probability (help please!)

Oh... it was just that ? I added it over like 4 times... I need to look at my formula sheet again. Thank you so much!!!!