My result was close: I said P(A) was the chance of dying by lighting strike (1/7,000,000), P(A|B) was the chance of dying if you knew the stat (1/6) and P(B) was the chance of knowing the stat (1/2,000,000). Plug 'em into Bayes and you get (1/6)*(1/2,000,000)/(1/7,000,000)=7/12 or 58%. Since I never studied Bayesian Statistics, though, I may be doing something wrong here.