You study for an exam, but due to the fact that you waited too long, you only learn 33% of the material. The exam is all multiple choice, with each question having 4 choices.
a) If you come across a question for which you don't know the answer, what's the probability of getting the answer right?
b) If you come across a question for which you do know the answer, what's the probability of getting it right (hint: don't “over think” this - what does it mean if you know the answer...)?
c) What is the overall probability of getting any question correct?