A multiple-choice test has 30 questions.There are 4 choices for each question.A student who has not studied for the test decides to answer all questions randomly.What type of probability distribution can be used to figure out his chance of getting at least 20 questions right?
A)binomial distribution.
B)Poisson distribution.
C)hypergeometric distribution.
D)none of the above.

Question

Quizplus · Accepted Answer

The situation described fits the criteria for a binomial distribution, which is used when there are a fixed number of independent trials with only two outcomes (success or failure) and a constant probability of success. In this case, answering a question correctly is a success or a failure with a probability of 0.25 for each option. The question asks for the probability of getting at least 20 questions right, which can be calculated using the binomial distribution formula.

A Multiple-Choice Test Has 30 Questions