Mathematics

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Aug 15, 2019 02:39
sup
Oct 11, 2017 16:02
Is that really the correct answer?
Oct 11, 2017 16:01
Then I saw the correct solution which uses stars and bars: There are \binom{15+4-1}{4-1} possible distributions for the passengers. Of all of them, only four correspond to the passengers getting off at a single stop(All at 1, All at 2...). Then the probability required would be 4/(\binom{18}{3})= 0.5% approx
Oct 11, 2017 15:58
In my first attempt, i said 'Well, each passenger, as a human being, chooses where to get off. So, for all to get off at stop 1, the probability would be (1/4)^15. Since there are 4 stops, the probability required would be (1/4)^14 which is approx. 0.0000003%
Oct 11, 2017 15:55
So, I had this problem of probability: In a bus there are 15 passenger and the bus makes 4 stops. Whats the probability that all 15 get off at the same stop?
Oct 11, 2017 15:52
hi
Oct 9, 2017 19:45
@LeakyNun I've got Dummit and Foot and it doesn't have comb
Oct 9, 2017 19:42
Does anyone have a recommendation on a book on groups that teaches applications to combinatorics? I already had a course on groups, but it was full abstract
Oct 9, 2017 19:40
does group theory have application on combinatorics?
Oct 9, 2017 17:53
@LeakyNun x^5-1 has 1 as solution.
Oct 9, 2017 17:51
?
Oct 9, 2017 17:51
@Albas How's that¡
Oct 9, 2017 17:49
want*
Oct 9, 2017 17:48
but again, this counts, for example, 1+1+1+1+96 as different from 96+1+1+1+1, and I don't wan't that.
Oct 9, 2017 17:47
whose formula is \binom{5+100-1}{100}
Oct 9, 2017 17:47
Then this is equivalent to put 100 balls in 5 numbered boxes.
Oct 9, 2017 17:46
And suppose I want non-negative integer solutions.
Oct 9, 2017 17:45
For example, suppose n=5.
Oct 9, 2017 17:45
I've just read the wiki and , as far as I see, it counts the tuples, and not the groups.
Oct 9, 2017 17:39
I really don't know the stars and bars method. I've always made combinatorial problems by "intuition" and knowing the classical formulas
Oct 9, 2017 17:38
Does it tell the number of distinct ones? I mean, I consider 1+2+97 the same as 97+1+2
Oct 9, 2017 17:37
I was wondering, is there any simple formula to know the number of distinct integer solutions to x_1+x_2+..+x_n=100?
Oct 9, 2017 17:16
hi
Apr 15, 2017 21:35
Hi
 

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Normally: General discussion around Ask Ubuntu, Ubuntu & offic...
Nov 6, 2016 20:55
Thanks
Nov 6, 2016 20:53
Nov 6, 2016 20:53
But I don't know how to "ping" it to you
Nov 6, 2016 20:52
Ok, done Thomas
Nov 6, 2016 20:28
would anybody here do me a favour? I wanted to comment a post to ask sthg but seems I don't have enough reputation... may someone comment by me?
Nov 6, 2016 20:23
Hi there
 

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General discussion for unix.stackexchange.com. If you have a q...
Oct 25, 2016 22:16
and never stops
Oct 25, 2016 22:16
it keeps giving me 6
Oct 25, 2016 22:15
do you know whats wrong with this: #!/bin/bash
i=1
while [ $i -le 10 ]
do
j=(5*$i)+1
echo "$j" | bc
done
Oct 25, 2016 22:13
?
Oct 25, 2016 22:13
anybody here¡