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 Feb 3 comment Probability of A Specific Type of Experiment Occuring Hmm, people just seemed to suddenly stop viewing this thread. Perhaps word got out that this is too boring of a problem. Feb 3 accepted Does the logical equivalence of 2 statements imply their semantic equivalence in everyday language? Feb 3 accepted Negating A Mathematical Statement Feb 3 accepted Simultaneous Equations and Vectors Feb 3 revised Probability of A Specific Type of Experiment Occuring edited tags Feb 3 asked Probability of A Specific Type of Experiment Occuring Feb 3 accepted Sodoku Puzzles and Propositional Logic Feb 3 comment Combinatorics Problem: To order or not to order. I'm sorry, I honestly can't see why you perform a combination and then multiply by $9!$. For a), I did a permutation and I got the same answer. For b), I did multiplied $P_{15,9} \cdot P_{15,9}$, but was off from the answer by a factor of 2 and I can't figure out why. Feb 2 comment Combinatorics Problem: To order or not to order. When you say, "...the list starts out as a list of the 9 playing positions (catcher, pitcher, first base, etc.)," does that correspond to ${{15}\choose{9}}$, which says out of the 15 positions how many ways can you arrange 9 of them? Feb 2 comment Combinatorics Problem: To order or not to order. Well, my book must be wrong: for a), the answer is 1,816,214,400; for b), the answer is 659,067,881,572,000; and for c), the answer is 9,072,000. Are all of these incorrect? Feb 2 comment Combinatorics Problem: To order or not to order. I'm having difficulty seeing why I am suppose to perform a permutation, instead of a combination, for part a. Call the players on the team $a,b,c,d,e,f,g,h,i,j,k,l,m,n,o$. Wouldn't this list for a 9-person starting line-up$a,b,c,d,e,f,g,h,i$ be the same as $i,h,g,f,e,d,c,b,a$? After all, it simply a a list of active players, and there order doesn't say anything about there position in the game. Feb 2 comment Combinatorics Problem: To order or not to order. Oh, I see. I didn't even know what a starting line-up was. So, the starting line-up is just a list of players who operate the bat, but in no particular order? Feb 2 comment Combinatorics Problem: To order or not to order. I'm sorry, but I don't see how it is clear. Feb 2 asked Combinatorics Problem: To order or not to order. Feb 2 comment Combinatorics Problem with Number of Web Sites Interesting, I'll keep this is problem in mind when I come to these mathematical tools you are alluding to. Feb 2 comment Combinatorics Problem with Number of Web Sites I'm not entirely sure. In my original post, I thought I was answering the question I posed of finding the number of domains where lexicographic ordering mattered. For instance, the first letter in your domain could be the letter b, and so a letter occupying the 2nd or third position couldn't be the letters a or b. So, b was the first letter, then there are 24 letter for the next choice and 23 letter for the third choice. Feb 2 comment Combinatorics Problem with Number of Web Sites I calculated that combination, which is 2600, and obviously its different from my answer, but not on a large magnitude. What is wrong with my procedure? Feb 2 comment Combinatorics Problem with Number of Web Sites Haha, yeah, I see. Feb 2 comment Combinatorics Problem with Number of Web Sites @BrianM.Scott Actually, now that you mention it, I am having trouble with part d. I thought the probability would simply be $97786/169616$, but it isn't. Feb 2 comment Combinatorics Problem with Number of Web Sites That's precisely what it is. Except, my last question was one that I had thought of myself.