When I saw a problem on the site, it had a 2.6 rating. Since I really liked the problem, I voted 5 for it, and saw that the rating went from 2.6 to 2.75.

1) How many people voted for it before I did?

2)What would the rating of this problem be if two more people voted 5 for this problem?

Let T = Total points for problem initially N= Number of voters initially we know T/N = 2.6 and (T+5)/(N+1) = 2.75, Simply subsitution shows (2.6N+5)/(N+1) = 2.75 -> 2.6N+5 = 2.75N + 2.75 reduces to .15N = 2.25 which shows 1) N = 15 which means T = 2.6*15 = 39 so 2) Simply calculation (39+15)/(18) = 3

Posted by Mr. Spock on 2003-07-26 08:50:44