1. The problem statement, all variables and given/known data I am having trouble reading this notation [tex]\sum[/tex] (i/k) The sum is from i=0 to n I wasn't sure how to write the combination of i,k on the computer so I just wrote it as i/k. 2. Relevant equations When I say combination I am talking about this formula n!/(k!(n-k)!) 3. The attempt at a solution Is this just (0/k)+(1/k)+(2/k)...(n/k) I am sure I am interpeting it wrong but If I am not what do you do for situations where n is less than k because when you do the combination you get n!/(k!(n-k)!), and I don't think it is possible to do a negative factorial.