On a multiple choice test of 10 questions, each question has 5 possible answers. A student is certain of the answers to 4 questions but is totally baffled by 6 questions. If the student randomly guesses the answers to those 6 questions, what is the probability that the student will get a score of 5 or more on the test. Express your answer correct to 2 decimal places.


I really don't know how to work this out because of 10 questions 5 possible answers is a bit confusing

He has to get at least one of the 6 correct in order to get the 5 score.

Find the prob. Of getting none of the 6 correct and subtract from 1.

The prob. Of getting a answer right is 1/5, therefore, the prob. Of getting it wrong is 4/5

The prob of getting at least 1 correct out of 6 is 1-(\frac{4}{5})^{6}