Posted by MathBard on October 21, 2002 at 22:43:41:
In Reply to: Re: probability; check me, someone! posted by Denis Borris on October 21, 2002 at 21:59:11:
: yep; assume one per second 6^12/(365*24*60*60) = 69 years !
: : : The hard part of the question is: How many ways can one add 12 integers
: : : that can range from 1 to 6 to get a value of 35 where order does make
: : : a difference (because of how the denominator has been calculated.)
: repeating: there are 197 "number combinations" that add up to 35.
: : TECHNICALLY there are 12 ways to roll a sum of 13.
: : any ONE of the twelve dice could roll a two. Here are three...
: : 1 1 1 1 1 1 1 1 1 1 1 2
: : 1 1 1 1 1 1 1 1 1 1 2 1
: : 1 1 1 1 1 1 1 1 1 2 1 1
: : etc.
: : Here is where i begin to lose it. With THIS in mind there is ONE combo for 12,
: : 12 combos for 13, and I THINK 122 combos for 14.
: agree with 12 and 13; but for 14, methinks it's 78:
: 1 1 1 1 1 1 1 1 1 1 1 3 : 12
: 1 1 1 1 1 1 1 1 1 1 2 2 : 66 ???????? You think it's 110 ?
: The way I get 66 is:
: the 2nd last 2 can move left spot by spot: 11
: the last 2 then moves 1+2+......+10
: sum 1 to 11 = 66.
: Testing the above "gem" on a shorter one:
: 1 1 2 2
: 1 2 1 2
: 1 2 2 1
: 2 1 1 2
: 2 1 2 1
: 2 2 1 1
: That's definitely 6; and 1+2+3 = 6
: BUT that'll only work with cases like x x x x ... x x x y y
: So that's not nuff for me to get a job at the crap table:)
I see the error in my calculations of 110+12 and i knew i was over my head at that point. My goal was to point out the difference in Mr.P's and your calculations, but i knew i needed help with probabliltity and summations.
I never took any college math, which is why i am here. i chime in on the easy ones but i am really herre to read everyone elses explanations.
MB