Need Math Help!! (7th grade math)

Here's the problem; I'm clueless. I know the answer from the back of the book but no idea how they got it.
"Annette, Rita, Sharmain, and Jana compete in the 100yard dash trackandfield event. How many different ways can the four of them finish first, second, third, and fourth? (Ignore ties.)"
HELP! Thanks. I hate this stuff. 



Oct 16, '02Well, I got out a pencil and piece of paper and was honestly going to attempt to figure it out....
But then I decided I simply didn't have the energy...
So do tell Shelly, how'd ya get 24? I'm thinking your baby is gonna be a little genius!
Heather 
Oct 16, '02OK, I got the answer but not on my own, LOL!
The answer is 24 and the calculation is 4 x 3 x 2 x 1. How they KNEW that, I have no idea.
If the runners were assigned letters ABCD, it would come out like this:
ABCD, ABDC, ACDB, ACBD, ADBC, ADCB
BACD, BADC, BCAB, BCDA, BDAC, BDCA,
CABD, CADB, CBDA, CBAD, CDAB, CDBA
DABC, DACB, DBAC, DBCA, DCAB, DCBA
WHEW!!! Now, except for kids' homework, when am I going to need to KNOW this?! 
Oct 16, '02OK........I just remembered this thingy from math...........where if you need to know the # of combinations possible (assuming they could all be arranged in any order....) then you multiply the # of factors (4) x every # below it.............
Like there are 4 competitors...........so 4x3x2x1= 24.........
does that make ANY sense? 
Oct 16, '02Cool, I only had them running 16 races, guess I wouldn't be a very good track coach..lol
OK, I'm ready for another question. 
Oct 16, '02Thanks, Shelley, it helps to know the rule!
You want another, mkue? There was another one that I puzzled over... 
Oct 16, '02you do 4! if you said it outloud that would read "Four factoral" which the "!" means you do 4x3x2x1
Brett 
Oct 16, '02Originally posted by mkue
Cool, I only had them running 16 races, guess I wouldn't be a very good track coach..lol
Heather 
Oct 17, '02Thanks, Brett.............couldn't remember it was called "factoral"............been a while since I was in math class............I can remember HOW to do it, but not WHY

Oct 17, '02Hmm. I don't remember and "!" being part of math class, but I was a big haired cigarette smoking rebel, so it's entirely possible I missed it.
Good to know though
Heather