Re: Position means for Powerball

On 10 Mar, 12:36, s...@[EMAIL PROTECTED]
 wrote:
> For 5/55 balls the means are all multiples of 1/3 and are
> 9 1/3 - 18 2/3 - 28 - 37 1/3 - 46 2/3
> The medians are 7-18-28-38-49
> The modes are 1-14-28-42-55

Let's generalise this, since I have been asked for more by email.  For
a selection of k balls from n possibilities which are then ordered,
the value of the position m ball (1<=m<=k<=n) has

mean:     m*(n+1)/(k+1)

variance: m*(n+1)*(n-k)*(k-m+1)/((k+1)^2*(k+2))