posted by Tanya on .
A student is taking a multiple choice exam. There are five possible answers for each question.
What is the probability the student will answer the first question correctly?
What is the probability that the student will answer the first question incorrectly?
assuming the student is totally ignorant of the subject matter, and guesses randomly, the the chance of a correct answer is 1/5.
That makes it easy to tell what the chance is of a wrong answer.
I'm not sure of the second question. I understand the 1/5 chance of answering correctly but I'm not sure of the probability of answering incorrectly. Would it be 1 - 1/5?