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  • New rule - no editing!

    This is my 200th post - I am going to turn yellow!

    I've noticed that editing of posts can sometimes make it difficult to see who answered first, or what a previous answer was etc. There will therefore be a new rule on this thread - for future questions, once an answer has been given, that post may not be edited, or it will be disqualified - in the same way as for The Statman's prediction competition. If you wish to change or clarify your answer, please paste it and amend it in a new post.

    Of course, that rule does not apply to me, if I need to clarify the wording of a question!
    "If anybody can knock these three balls in, this man can."
    David Taylor, 11 January 1982, as Steve Davis prepared to pot the blue, in making the first 147 break on television.

    Comment


    • Originally Posted by davis_greatest
      This is my 200th post - I am going to turn yellow!

      I've noticed that editing of posts can sometimes make it difficult to see who answered first, or what a previous answer was etc. There will therefore be a new rule on this thread - for future questions, once an answer has been given, that post may not be edited, or it will be disqualified - in the same way as for The Statman's prediction competition. If you wish to change or clarify your answer, please paste it and amend it in a new post.

      Of course, that rule does not apply to me, if I need to clarify the wording of a question!
      Double standards!



      Just kidding
      ZIPPIE FOR CHAIRMAN

      Comment


      • well, well, so I did get it right in the end. Rather encouraging. I had to correct about 5, 6 minor calculation mistakes though... could get quite embarrasing to post so many wrong answers.
        anyway, have to sit some out in the future, as workload will defo increase quite soon

        Comment


        • Originally Posted by April madness
          Double standards!



          Just kidding
          You think THAT'S unfair? Wait till you see me award myself 20 points!
          "If anybody can knock these three balls in, this man can."
          David Taylor, 11 January 1982, as Steve Davis prepared to pot the blue, in making the first 147 break on television.

          Comment


          • Originally Posted by snookersfun
            well, well, so I did get it right in the end. Rather encouraging. I had to correct about 5, 6 minor calculation mistakes though... could get quite embarrasing to post so many wrong answers.
            anyway, have to sit some out in the future, as workload will defo increase quite soon
            How did you get your answer of 2033?
            "If anybody can knock these three balls in, this man can."
            David Taylor, 11 January 1982, as Steve Davis prepared to pot the blue, in making the first 147 break on television.

            Comment


            • Just when I thought, I am exempt from giving explanations.
              wrote them all up.... lol


              No, well wrote up all the possible kind of combinations
              e.g. 10,2;
              10,1,1;
              8,3,1
              8,2,2,
              8,2,1,1, etc. you get the drift

              and then calculated for each of these the possible permutations,
              actually using the formula for possible permutations:
              # of rearrangements for n numbers, k1,k2,...kn, types:
              = n!/(k1!k2!...kn!)

              and then made 100 possible mistakes in adding them all up...

              I am sure, you'll have a shorter way, let me know, would love to learn!

              Comment


              • Wow! That must have taken you a while?!

                I'll post my way in a short while.
                "If anybody can knock these three balls in, this man can."
                David Taylor, 11 January 1982, as Steve Davis prepared to pot the blue, in making the first 147 break on television.

                Comment


                • Originally Posted by davis_greatest
                  You think THAT'S unfair? Wait till you see me award myself 20 points!
                  Only if you award me at least 19
                  ZIPPIE FOR CHAIRMAN

                  Comment


                  • Originally Posted by davis_greatest
                    Wow! That must have taken you a while?!

                    I'll post my way in a short while.
                    less than 1 h , with quite a lot of work related disturbances as well

                    I am sure there exists a formula to reach a certain value from possible types of values. e.g. use all the values for 1-10 to reach 12 and just substract the possibilities including 9 (which is really only missing). Just would have taken me longer to find this formula, I would think.

                    Comment


                    • OK, when I originally explained this on the BBC site (I made the question a bit easier then), I did it with matchsticks and lemons. So I'll use matchsticks and lemons again...

                      Suppose first of all that there were a ball available of every possible value from 1 to 12 (rather than just 1,2,3,4,5,6,8,10 and 12) - then let's count how many ways.

                      You can do this by representing every sequence using 12 lemons (0), with some matchsticks (!) separating them to correspond to the value of each ball potted.

                      For example, blue-black (5-7) would be represented by 5 lemons, matchstick, 7 lemons, as follows:

                      0 0 0 0 0 ! 0 0 0 0 0 0 0

                      12 reds would be shown as lemon, matchstick, lemon, matchstick, lemon, matchstick, lemon, matchstick, lemon, matchstick, lemon, matchstick, lemon, matchstick, lemon, matchstick, lemon, matchstick, lemon, matchstick, lemon, matchstick, lemon:

                      0 ! 0 ! 0 ! 0 ! 0 ! 0 ! 0 ! 0 ! 0 ! 0 ! 0 ! 0

                      So the number of sequences is just the number of ways of putting or not putting a matchstick in each of the 11 gaps between lemons, i.e.

                      2^11 = 2048 ways.

                      Now remember that in Snooker Plus there are no balls worth 12, 11 or 9 points, so some of the ways are impossible. These are:

                      a) using a 12-ball ------------------> 1 way
                      b) using an 11-ball -----------------> 2 ways (11-1 or 1-11)
                      c) using a 9-ball:
                      (i) with a 3-ball -------------------> 2 ways (9-3 or 3-9)
                      (ii) with a 2-ball and a 1-ball -------> 3! = 6 ways (1-2-9 or 1-9-2 or 2-1-9 or 2-9-1 or 9-1-2 or 9-2-1)
                      (iii) with three 1-balls --------------> 4 ways (9-1-1-1 or 1-9-1-1 or 1-1-9-1 or 1-1-1-9)

                      Total impossible ways: 1+2+2+6+4 = 15

                      So we need to deduct 15 ways from 2048, and arrive at 2033.

                      PS I wanted to use as lemons, but I am not allowed to use more than 4 smileys in a message, apparently!
                      "If anybody can knock these three balls in, this man can."
                      David Taylor, 11 January 1982, as Steve Davis prepared to pot the blue, in making the first 147 break on television.

                      Comment


                      • Originally Posted by April madness
                        Only if you award me at least 19
                        Perhaps I'll award you 10 points if you ask very nicely.
                        "If anybody can knock these three balls in, this man can."
                        David Taylor, 11 January 1982, as Steve Davis prepared to pot the blue, in making the first 147 break on television.

                        Comment


                        • Originally Posted by davis_greatest
                          Perhaps I'll award you 10 points if you ask very nicely.
                          that'll be the day I stop breaking my head to answer questions on this thread

                          and you think playing with matchsticks and lemons would have been faster-lol







                          seriously though- impressive

                          Comment


                          • Snookersfun, I am sure if you ask DG very nicely he'll award you points too
                            ZIPPIE FOR CHAIRMAN

                            Comment


                            • nah, he didn't want to do my ironing either...
                              maybe, you'll ask him for me...

                              Comment


                              • Originally Posted by snookersfun
                                nah, he didn't want to do my ironing either...
                                maybe, you'll ask him for me...
                                OK, bring on all your ironing, everyone! April will collect it all in bags in her "Anything exciting today?" thread and I'll get it done there.
                                "If anybody can knock these three balls in, this man can."
                                David Taylor, 11 January 1982, as Steve Davis prepared to pot the blue, in making the first 147 break on television.

                                Comment

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