you take a three-question multiple-choice test.each question has four choices.you don't know any of the answers. what is the experimental probability that you will guess exactly two out of three correctly

please help me i am confused

2 answers

right = r
wrong = w

so you want
rrw
rwr
wrr
each of the above has a prob of 1/4 x 1/4 x 3/4 = 3/16

so the prob of getting 2 out of 3 correct is 3(3/16) = 9/16
that should have said:

each of the above has a prob of 1/4 x 1/4 x 3/4 = 3/64

so the prob of getting 2 out of 3 correct is 3(3/64) = 9/64