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?
The problem can be solved by setting up a system of equations.
Given x=the sum of the ratings and y=the number of people who have rated, then:
x/y=2.6
x+5/y+1=2.75
Thus, x=2.6y
2.6y+5/y+1=2.75
2.6y+5=2.75y+2.75
5=.15y+2.75
2.25=.15y
y=15
1) 15 people had voted before with the a ratings sum of 39.
2) If two more people voted
before you then the rating would be 2.9.
If two more people voted
after you then the rating would be 3.