1. ## ??

is this a permutation of combination?

from a committee of fifteen members, president, vice president, and treasure are elected. In how many ways can this be accomplished?

would i just do: 15!/(15-3)!

or this: 15!/(15-3)!3!

or neither? & something else...

any thoughts or help would be great!

2. Originally Posted by sevenlovesyou
is this a permutation of combination?

from a committee of fifteen members, president, vice president, and treasure are elected. In how many ways can this be accomplished?

would i just do: 15!/(15-3)!

or this: 15!/(15-3)!3!

or neither? & something else...

any thoughts or help would be great!
Note that $_nC_r=\frac{n!}{r!(n-r)!}$.

So what you want is $_{15}C_3=\frac{15!}{3!(12!)}$

--Chris

3. Originally Posted by Chris L T521
So what you want is $_{15}C_3=\frac{15!}{3!(12!)}$
No actually in this case the answer is $_{15}P_{3}=(15)(14)(13)$.

4. ## thanks

thanks! so much. so is it a combination or permentation?

5. It is a permutation because there you are considering people in a specific order. For example, a committee with John as the president and a commitee with John as a treasurer are different. Order matters.

6. ## thanks!

wow! thanks so much!