Question 667035
Whenever you see the word "at least" think about the complement. It is much easier to calculate the probability of "none" than "all other possibilities". What is the probability that you get no answers right at all?

P[none]= (1/2)^8

So P[at least correct] = 1 - P[none correct] = 1 - (1/2)^8 = .9961