Evaluate P(5, 3).

Question

Evaluate P(5, 3).

abb0t · Answer

|dw:1368594782173:dw|

anonymous · Answer

?

e.mccormick · Answer

He is thinking P ans in Point, but this is probability?

anonymous · Answer

this is permutations

e.mccormick · Answer

$$P(n,r) = \frac{n!}{(n-r)!}$$

anonymous · Answer

I think it's the other formula: $$P(n,n)=n!$$

e.mccormick · Answer

They are not the same number.

anonymous · Answer

oh, k I'm lost

e.mccormick · Answer

In n permutations of n objects, it is n!.  But here the objects and permutations are different.

anonymous · Answer

I understand the formula's but I'm lost on what to do next

e.mccormick · Answer

Know what the factorial ! is?

anonymous · Answer

nope, but I'm assuming the next step is$$\frac{ n! }{ (4-3)! }$$

anonymous · Answer

i mean 5, 3

e.mccormick · Answer

huh?  What happened to the 5?

e.mccormick · Answer

Ah, kk.

anonymous · Answer

lol

e.mccormick · Answer

$7!=7\cdot 6\cdot 5\cdot 4\cdot 3\cdot 2\cdot 1$

anonymous · Answer

n!/2!

abb0t · Answer

oHhHhH.! my bad. Lol

anonymous · Answer

lol

abb0t · Answer

i don't rmr this. Lol

e.mccormick · Answer

Well, your n is 5, so... 5!/2! and the factors cancel, so that means there is a little bit you won't need to multiply out.

anonymous · Answer

oh...fail, lol I was confused on that part. Thanks, got it from there

e.mccormick · Answer

What happened to the red cat avatar?

anonymous · Answer

got bored with it

e.mccormick · Answer

Ah. Some change a lot... other seem to stay the same.

anonymous · Answer

indeed, but I was never the grumpy cat so I guess I changed back to being the same

e.mccormick · Answer

So you are the cute girl, but are not the grumpy cat.  Hehe.  Well, the grumpy cat was different, so I wondered.

anonymous · Answer

lol, I wish I was that sexy, but no grumpy cat is the one and only grumpy cat.

e.mccormick · Answer

There are a lot of "cute girl" avatars on here...  most can image search to very public images.... which means they are being used by people other than the cute girl.  LOL.

anonymous · Answer

hmm, interesting...makes you wonder if I'm really me? o-o or am I a man named bob with a beard, seven dogs, who hitch-hikes into town on the wednesdays...which one am I really? 0-0

e.mccormick · Answer

Depends.... do you like pancakes?

anonymous · Answer

YES I LIKE PANCAKES

anonymous · Answer

do you like waffles?

e.mccormick · Answer

Hmmm.... depends on the waffles.

anonymous · Answer

darn, you don't know the song

e.mccormick · Answer

$$P(n,r) = \frac{n!}{(n-r)!}\ \implies
P(n,r) = \frac{5!}{2!}\ \implies
P(n,r) = \frac{5\cdot 4\cdot 3\cdot 2}{2}\ \implies
P(n,r) = 5\cdot 4\cdot 3\ \implies
P(n,r) = 60$$Yah, not so hard when you know the !.

anonymous · Answer

so that at least means I'm not you...

e.mccormick · Answer

Ah, I do not know the song.  Yep.

anonymous · Answer

and...wuuuuuuut?

anonymous · Answer

I got 20 as my answer

e.mccormick · Answer

If it was 5!/3! it would be 20.

anonymous · Answer

isn't it?

e.mccormick · Answer

$2!=2\times 1$ and 1 never matters...

anonymous · Answer

oh, different question, lol

e.mccormick · Answer

$(n-r)=(5-3)\implies 2$ Ah, but a different question would have a different answer.  So yah, the other question might be 20!

anonymous · Answer

i thought so...lol

e.mccormick · Answer

http://www.youtube.com/watch?v=HZdS4973Axw&noredirect=1 Well, now I know the song. =P

anonymous · Answer

lol, so i might be u now...i could be everyone and no one at the same time...like vendetta

e.mccormick · Answer

Ah, but can you explain the Cartesian Circle?  Which as much as that sounds like math, is not!

anonymous · Answer

does that have anything to do with royalty?

e.mccormick · Answer

Descartes Ontological argument.  Descartes, the man we named the Cartesian Plane after because of how he used it in math, was also a philosopher... in fact, he may never have considered himself a mathematician, Philosophy having been his primary reason for studying math.

anonymous · Answer

oh I've heard of him, forgot about itlast year

e.mccormick · Answer

Forget Descartes... ... ....  How?  =P  He is such a foundation of our society that he is quoted every day!  Cogito ergo sum! I think, therefore I am!

anonymous · Answer

it's easy to forget when it's knocked out of your head....a pan just fell from the cabinet and hit it's target...

e.mccormick · Answer

I see, so now the pan has taken a personal affront to Descartes and knocked him out of your head.  Hmmm...  You are Bob with a beard, seven dogs, who hitch-hikes into town on the wednesdays!

anonymous · Answer

o-o now I remember!

e.mccormick · Answer

hehehe

anonymous · Answer

who are you??

e.mccormick · Answer

I am me!  That name there is actually mine.

anonymous · Answer

You own mccormick seasonings?? o-o

e.mccormick · Answer

Nope.  But I am a Grandson of the Chariot by birth, if you know the meaning of McCormick.

anonymous · Answer

nope not at all,