Its easier to find the complement of that instead so you find the probability of 1 and 0 The .2 in the answer is the probability of each question 1/5 (10 C 0) x .2^0 (1-.2)^10-0=.1074 (10 C 1) x .2^1 (1-.2)^10-1=.2684 .2684+.1074=.3758 and that's the complement so 1 - .3758= .6242 I too have a stats exam on this tomorrow lol
