I need help in this probability problems.
This seems like simple, and I tried using the normal probability rule but I was told that this is to be done my binomial, which makes me stuck.
On a given multiple choice test, there are 4 questions, each with 4 possible answers. Say you take the test by guessing randomly on each question.
1. How many questions would you expect to get right?
2. What’s the probability that you get all four questions correct?
3. What’s the probability that you get at least 2 questions correct?
Thanks a lot!