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)Either of the above
D)none of the above.

Question

Quizplus · Accepted Answer

The situation described fits a binomial distribution because there are a fixed number of trials (30 questions), each trial has only two possible outcomes (correct or incorrect), the probability of success (getting a question right) is constant (1/4), and the trials are independent.

A Multiple-Choice Test Has 30 Questions