Nah Fez had his math right, it might be a little tricky to understand.
Basically you are adding up the probabilites that Fez wins 3-0 or 2-1 in the 3 trials.
First, brush up on combinatorial math: [url]https://en.wikipedia.org/wiki/Combination[/url]
so let's write n choose k as (n,k)
and let's say x = .515 to make this easier
Prob of 3-0 = (3,0) * x^3
Prob of 2-1 = (3,1) * x^2 * (1-x)
Add those up and you get your 52.25
You can also calculate the probability of the other outcomes as follows:
Prob of 1-2 = (3,2) * x * (1-x)^2
Prov of 0-3 = (3,3) * (1-x)^3